Layered double hydroxide- and graphene-based hierarchical nanocomposites： Synthetic stra

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1T型二硫化钼的制备与应用现状

Vol.7 No.2Apr. 2021生物化工Biological Chemical Engineering第 7 卷第 2 期2021 年 4 月1T 型二硫化钼的制备与应用现状汪芃，刘圆圆，武钰，刘晓文*（中南大学资源加工与生物工程学院，湖南长沙 410083）摘要：1T 型二硫化钼（MoS 2）具有较高的导电率和较宽的离子扩散通道，有利于电化学储能中的电子传输和离子扩散，因此光电催化性能优异，但因亚稳定性而导致实际应用受到了限制。

本文归纳了1T 型MoS 2的制备及改性方法，介绍了1T 型MoS 2在超级电容器、电池及电催化析氢等领域的应用。

关键词：1T 型MoS 2；制备方法；应用中图分类号：TB32 文献标识码：APreparation and Applications Status of 1T-phase MoS 2WANG Peng, LIU Yuanyuan, WU Yu, LIU Xiaowen *(School of Minerals processing and Bioengineering, Central South University, Hunan Changsha 410083)Abstract: 1T-phase Molybdenum Disulfide (MoS 2) has high conductivity and wide ion diffusion channel, which is conducive to the electron transport and ion diffusion in electrochemical energy storage, so it has excellentphotoelectrocatalytic performance, but its practical application is limited due to its metastability. This paper summarizes the preparation and modification methods of 1t type MoS 2, and introduces the application of 1t type MoS 2 in supercapacitor, battery and electrocatalytic hydrogen evolution.Keywords: 1T-Phase MoS 2; preparation method; applications二维层状过渡金属硫族化合物物理化学性质独特，近年来被人们进行广泛的研究[1]。

“Graphene”研究及翻译

“Graphene”研究及翻译摘要：查阅近5年我国SCI、EI期源刊有关石墨烯研究873篇，石墨烯研究的有关翻译存在很大差异。

从石墨烯的发现史及简介，谈石墨烯内涵及研究的相关翻译。

指出“石墨烯”有关术语翻译、英文题目、摘要撰写应注意的问题。

关键词：石墨烯；石墨烯术语；翻译石墨烯是目前发现的唯一存在的二维自由态原子晶体，它是构筑零维富勒烯、一维碳纳米管、三维体相石墨等sp2杂化碳的基本结构单元，具有很多奇异的电子及机械性能。

因而吸引了化学、材料等其他领域科学家的高度关注。

近5年我国SCI、EI期源刊研究论文873篇，论文质量良莠不齐，发表的论文有35.97%尚未被引用过，占国际论文被引的4.84%左右。

石墨烯研究的有关翻译也存在很大差异。

为了更好的进行国际学术交流，规范化专业术语。

本文就“graphene”的内涵及翻译谈以下看法。

l “Graphene”的发现史及简介1962年，Boehm等人在电镜上观察到了数层甚至单层石墨（氧化物）的存在，1975年van Bom-mel等人报道少层石墨片的外延生长研究，1999年德克萨斯大学奥斯汀分校的R Ruoff等人对用透明胶带从块体石墨剥离薄层石墨片的尝试进行相关报道。

2004年曼彻斯特大学的Novoselov和Geim小组以石墨为原料，通过微机械力剥离法得到一系列叫作二维原子晶体的新材料——石墨烯，并于10月22日在Sclence期刊上发表有关少层乃至单层石墨片的独特电学性质的文章，2010年Gelm和No-voselov获得了诺贝尔物理学奖。

石墨烯有着巨大的比表面积（2630 m2/g）、极高的杨氏模量（1.06 TPa）和断裂应力（～130GPa）、超高电导率（～106 S/cm）和热导率（5000W/m·K）。

石墨烯中的载流子迁移率远高于传统的硅材料，室温下载流子的本征迁移率高达200000 cm2/V.s），而典型的硅场效应晶体管的电子迁移率仅约1000 cm2/V.s。

层状双氢氧化物基复合材料的制备及其电化学性能的研究

层状双氢氧化物基复合材料的制备及其电化学性能的研究The Construction of Layered Double Hydroxides-Based Hybrid Materials for Electrochemical ApplicationAbstractTwo-dimensional (2D) materials have attracted increasing interest in electrochemical energy storage andconversion. As typical 2D materials, layered double hydroxides (LDHs) display large potential in this areadue to the facile adjustableof their composition, structure and morphology. Various preparationstrategies, including in situ growth, electrodeposition and layer-by-layer (LBL) assembly, have beendeveloped to directly modify electrodes by using LDHs materials. Moreover, several composite materialsbased on LDHs and conductive matrices have also been rationally designed and employed in supercapacitors, batteries and electrocatalysis with largely enhanced performances.This paper focus on the construction of LDHs-based composites and its application in electrocatalytic hydrolysis and electrochemical energy storage carried out in a series of trial and research.The controllable synthesis of LDHs-based composites was realized by the method of multi-step hydrothermal process and liquid phase self-assembly. As a result, the electrochemical performance was enhanced.The main contents of this paper are as following:(1) Study on the construction of NiFe LDH@NiCo2O4 compositesHerein, for the first time, we demonstrate NiFe-LDH ultrathin sheets with several atomic layers grown on nickel cobalt oxide (NiCo2O4) nanowire arrays as an efficient bifunctionalcatalyst toward both HER and OER reaction. Nickel (Ni) foam was used as the electrode scaffold support because of its earth abundance and porous three-dimensional structure.NiCo2O4, a typical OER electrocatalyst with high conductivity, was deposited on the Ni foam in the form of rhombus/hexagonal plates interconnected into perpendicular nanowire array morphology, efficientlyfacilitating electron transfer and electrolyte permeation. The electrical conductivity in NiCo2O4 has been believed to originate from the层状双氢氧化物基复合材料的制备及其电化学性能的研究presence of Ni3+ and the electron transfer between Ni2+ and Ni3+. Importantly, the surface of NiCo2O4was a Ni-rich layer, which served as the seed for the following hierarchical growth of NiFe-LDH, ensuring close contact and strong coupling at the interface.(2) Study on the properties of electrocatalytic water splitting of NiFe LDH@NiCo2O4 compositesHerein, the NiFe-LDH sheets were ultrathin of only several atomic layers, combined with its strong coupling with NiCo2O4 and the unique hierarchical structure, enabled the hybrid electrode a remarkable overall water splitting performance of only 1.60 V to achieve 10 mA cm-2 current in single alkaline KOH eletrolyte.Key words: Layered double hydroxides (LDHs)，Electrocatalysis, Overall water splitting, Hydrogen evolution reaction, Oxygen evolution reaction，Heterostructure.Written by: Zhiqiang WangSupervised by: Prof. Fengxia GengProf. Xingwang Wang目录第一章文献综述 (1)1.1 引言 (1)1.2 LDHs及其复合材料的制备 (2)1.2.1 LDHs的基本结构 (2)1.2.2 LDHs的制备方法 (2)1.3 LDHs及其复合材料的应用 (3)1.3.1电催化水解中的应用 (3)1.3.2超级电容器中的应用 (10)1.4论文的选题思路、意义和主要工作 (15)1.4.1选题思路和意义 (15)1.4.2主要工作 (16)参考文献 (16)第二章超薄NiFe LDH纳米片与NiCo2O4纳米线杂化结构的构筑 (16)2.1 引言 (24)2.2 实验部分 (26)2.2.1 实验试剂 (26)2.2.2 仪器 (26)2.2.3 实验步骤 (27)2.3 结果与讨论 (28)2.3.1 SEM分析 (28)2.3.2 XRD和BET分析 (30)2.3.3 TEM分析 (32)2.3.4 EDS和Mapping分析 (33)2.3.5 XPS分析 (35)2.4 小结 (37)参考文献 (37)第三章NiFe LDH@NiCo2O4杂化结构的电催化全解水性能研究 (41)3.1 引言 (41)3.2 实验部分 (41)3.2.1 电化学测试 (41)3.3 结果与讨论 (42)3.3.1析氧反应分析 (42)3.3.2析氢反应分析 (44)3.3.3 全解水分析 (45)3.3.4 CV和EIS分析 (46)3.3.5电催化性能比较 (47)3.3.6 电催化性能的机理探究 (50)3.4 小结 (53)参考文献 (53)第四章结论和展望 (53)4.1 全文总结 (60)4.2 展望 (60)在读期间已发表或录用的论文 (62)致谢 (63)第一章文献综述1.1 引言能源在当今社会的发展中发挥着重要的作用，但近年来由传统能源煤、石油、天然气等资源的日益消耗，以及化石燃料等的大量使用所带来的生活环境的污染，以及温室气体的增加导致的海平面上升、酸雨的形成，使人类面临生存环境的恶化，不可再生能源的枯竭等多重威胁1-4。

氧化石墨烯稳定的Pickering乳液及其性能研究的文献综述

氧化石墨烯稳定的Pｉckｅrｉnｇ乳液及其性能研究的文献综述专业:高分子材料与工程班级:１0级(涂料方向)作者：梅梦凡导师:申亮教授摘要:简述了石墨烯的结构特征，制备方法;氧化石墨烯的几种制备方法;Pickering 乳液的稳定机理及影响稳定性的因素，并探讨Piｃkerｉng乳液的研究现状及对未来的展望。

关键词：石墨烯;氧化石墨烯;Pickｅｒiｎg乳液；稳定性碳原子人类最早认识的构成一切生物机体的主要之一，而自20０4年石墨烯被发现以来，这种由层碳原子紧密堆积而成的二维蜂窝状的晶格结构的碳质材料,因为其优异的性能而越来越受到人们的关注与研究[1].作为石墨烯的前驱体的氧化石墨烯也备受关注,氧化石墨是通过强氧化剂氧化石墨而制得的一种石墨衍生物。

目前，主要有三种制备氧化石墨的方法:Ｂrｏdiｅ，Ｓｔauｄeｎｍａier和Hｕｍmｅrs法，其中Hummeｒｓ方法因其应时间短，反应过程简单,对环境污染小和安全性高等优点成为目前普遍采用的方法之一。

本文采用改进的Ｈｕｍmer法制得的氧化石墨烯来稳定Piｃkeｒiｎg乳液,并探究该乳液的性能。

Pｉckeriｎg乳液是采用固体粒子代替有机乳化剂来稳定乳液的一种新型乳液,影响乳液稳定性的因素来源于对固体颗粒直接或间接的影响［2,３];随着纳米技术的发展,国内外对其进行更加深入和广泛的研究从而在生产中表现出巨大的潜力.1 石墨烯１。

1 石墨烯的结构200４年，英国Manchｅｓｔer大学的Gｅiｍ等人通过胶带反复剥离石墨片(微机械力分离法)得到只有一个原子厚度的石墨单片—石墨烯(grａｐhene)［1]．图１.石墨烯的结构示意图[１]单层的石墨烯是二维晶体结构,在平面内，碳原子以六元环的形式进行周期性的有序的排列，形成蜂窝状的晶格结构。

199１年被日本人［４］发现的碳纳米管,可以看做是由石墨烯卷曲形成的一维结构[1],[５],１985年被美国人［6］发现的富勒烯可以看做是由石墨烯团聚而成的零维结构[7],而三维的石墨则可以看做是由三层的石墨烯片有序的堆积而成[8],因此，石墨烯可以看做是其他维度的碳材料的基本结构单元。

Ni－Fe LDH的电沉积制备及其电催化氧析出性能

Ni－Fe LDH的电沉积制备及其电催化氧析出性能徐梦莹;孟玲袆;王雅静;刘洪涛【摘要】氧析出反应（ OER）是阳极电解水的关键步骤。

提出了一种简单可控的一步电沉积制备Ni－Fe LDH的方法，并成功用于电催化OER反应。

结果表明，在－1�1 V条件下，采用1∶1镍铁摩尔比，沉积液总浓度为0�12 M时沉积300 s所得Ni－Fe LDH薄膜催化剂具有高的OER催化活性（在10 mA／cm2电流密度下的过电位为220 mV）、快的反应动力学（塔菲尔斜率为44�9 mV／dec）和优良的催化稳定性（持续极化10 h仅衰减2�5％）。

%Oxygen evolution reaction ( OER) is the key step for water splitting at anode. The paper presents a simple and controllable method for one-step synthesis of nickel-iron layered double hydroxide ( Ni-Fe LDH ) as a potential OER electrocatalyst. It is found that the Ni-Fe LDH deposited under the optimal conditions ( deposition time: 300 s; deposition potential: -1.1V;Ni2++Fe3+total concentration:0.12 M;Ni/Fe ratio:1∶1) demonstrateshigh catalytic activity ( overpotential 220 mV at 10 mA/cm) , fast reaction dynamics ( Tafel slope 44.9 mV/dec) , and excellent stability ( retaining 97.5% after 10 h) toward OER reaction.【期刊名称】《龙岩学院学报》【年(卷),期】2016(034)005【总页数】5页(P24-28)【关键词】电沉积;层状双金属氢氧化物;电催化;氧析出反应【作者】徐梦莹;孟玲袆;王雅静;刘洪涛【作者单位】中南大学湖南长沙 410083;中南大学湖南长沙 410083;中南大学湖南长沙 410083;中南大学湖南长沙 410083【正文语种】中文【中图分类】O646随着传统化石燃料的大量消耗，能源紧缺的问题愈发突出，寻找可替代的清洁能源成为科学家们研究的热点课题之一［1］。

Liquid_Exfoliation_of_Layered_Materials

DOI: 10.1126/science.1226419, (2013);340 Science et al.Valeria Nicolosi Liquid Exfoliation of Layered MaterialsThis copy is for your personal, non-commercial use only.clicking here.colleagues, clients, or customers by , you can order high-quality copies for your If you wish to distribute this article to othershere.following the guidelines can be obtained by Permission to republish or repurpose articles or portions of articles): July 3, 2013 (this information is current as of The following resources related to this article are available online at/content/340/6139/1226419.full.html version of this article at:including high-resolution figures, can be found in the online Updated information and services, /content/340/6139/1226419.full.html#ref-list-1, 8 of which can be accessed free:cites 136 articles This article/cgi/collection/chemistry Chemistrysubject collections:This article appears in the following registered trademark of AAAS.is a Science 2013 by the American Association for the Advancement of Science; all rights reserved. The title Copyright American Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by the Science o n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mThe list of author afﬁ liations is available in the full article online.*Corresponding author. E-mail: colemaj@tcd.ieLiquid Exfoliation of Layered MaterialsValeria Nicolosi, Manish Chhowalla, Mercouri G. Kanatzidis, Michael S. Strano, Jonathan N. Coleman*Background: Since at least 400 C.E., when the Mayans ﬁ rst used layered clays to make dyes, people have been harnessing the properties of layered materials. This gradually developed into scientiﬁ c research, leading to the elucidation of the laminar structure of layered materials, detailed understand-ing of their properties, and eventually experiments to exfoliate or delaminate them into individual, atomically thin nanosheets. This culminated in the discovery of graphene, resulting in a new explosion of interest in two-dimensional materials.Layered materials consist of two-dimensional platelets weakly stacked to form three-dimensional structures. The archetypal example is graphite, which consists of stacked graphene monolayers. How-ever, there are many others: from MoS 2 and layered clays to more exotic examples such as MoO 3, GaTe, and Bi 2Se 3. These materials display a wide range of electronic, optical, mechanical, and electrochemi-cal properties. Over the past decade, a number of methods have been developed to exfoliate layered materials in order to produce monolayer nanosheets. Such exfoliation creates extremely high-aspect-ratio nanosheets with enormous surface area, which are ideal for applications that require surface activity. More importantly, however, the two-dimensional conﬁ nement of electrons upon exfoliation leads to unprecedented optical and electrical properties.Advances: An important advance has been the discovery that layered crystals can be exfoliated in liquids. There are a number of methods to do this that involve oxidation, ion intercalation/exchange, or surface passivation by solvents. However, all result in liquid dispersions containing large quantities of nanosheets. This brings considerable advantages: Liquid exfoliation allows the formation of thin ﬁ lms and composites, is potentially scaleable, and may facilitate processing by using standard technologies such as reel-to-reel manufacturing.Although much work has focused on liquid exfoliation of graphene, such processes have also been demonstrated for a host of other materials, including MoS 2 and other related structures, lay-ered oxides, and clays. The resultant liquid dispersions have been formed into ﬁ lms, hybrids, and composites for a range of applications.Outlook: There is little doubt that the main advances are in the future. Multifunctional composites based on metal and polymer matrices will be developed that will result in enhanced mechanical, electrical, and barrier properties. Applications in energy generation and storage will abound, with layered materials appearing as electrodes or active elements in devices such as displays, solar cells, and batteries. Particularly impor-tant will be the use of MoS 2 for water splitting and metal oxides as hydrogen evolution catalysts. In addition, two-dimensional materials will ﬁ nd important roles in printed electronics as dielectrics, optoelectronic devices, and transistors.To achieve this, much needs to be done. Production rates need to be increased dramatically, the degree of exfoliation improved, and methods to control nanosheet properties devel-oped. The range of layered materials that can be exfoliated must be expanded, even as methods for chemical modiﬁ cation must be developed. Success in these areas will lead to a family of materials that will dominate nanomaterials science in the 21st century.21 JUNE 2013 VOL 340 SCIENCE 1420ARTICLE OUTLINE Why Exfoliate?Large-Scale Exfoliation in Liquids?PioneersRecent Advances in Liquid Exfoliation Potential Applications of Liquid-Exfoliated Nanosheets OutlookADDITIONAL RESOURCESJ. N. Coleman et al ., Two-dimensional nanosheets produced by liquid exfoliation of layered materials. Science 331, 568–571 (2011). doi:10.1126/science.1194975K. Varoon et al ., Dispersible exfoliated zeolite nanosheets and their application as a selective membrane. Science 334, 72–75 (2011). doi:10.1126/science.1208891READ THE FULL ARTICLE ONLINE /10.1126/science.1226419Liquid exfoliation of layered crystals allows the production of suspensions of two-dimensional nanosheets, which can be formed into a range of structures. (A ) MoS 2 powder. (B ) WS 2 dispersed in surfactant solution. (C ) An e xfoliate d MoS 2 nanosheet. (D ) A hybrid material consisting of WS 2 nanosheets embedded in a network of carbon nanotubes.Published by AAASo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mLiquid Exfoliation of Layered Materials Valeria Nicolosi,1,2Manish Chhowalla,3Mercouri G.Kanatzidis,4Michael S.Strano,5Jonathan N.Coleman1*Not all crystals form atomic bonds in three yered crystals,for instance,are those that form strong chemical bonds in-plane but display weak out-of-plane bonding.This allows them to be exfoliated into so-called nanosheets,which can be micrometers wide but less than a nanometer thick.Such exfoliation leads to materials with extraordinary values of crystal surface area,in excess of1000square meters per gram.This can result in dramatically enhanced surface activity,leading to important applications,such as electrodes in supercapacitors or batteries. Another result of exfoliation is quantum confinement of electrons in two dimensions,transforming the electron band structure to yield new types of electronic and magnetic materials.Exfoliated materials also have a range of applications in composites as molecularly thin barriers or as reinforcing or conductive fillers.Here,we review exfoliation—especially in the liquid phase—as a transformative process in material science,yielding new and exotic materials,which are radically different from their bulk,layered counterparts.I n1824,Thomas H.W ebb heated a mineral sim-ilar to mica and,by means of thermal ex-foliation,transformed it into what is today a valuable commodity,with applications as an ion exchange resin,an insulating material,and a structural binder in cement.He named the mineral“vermiculite”for its wormlike appear-ance upon exfoliation(Fig.1),from the Latin vermiculare meaning“to breed worms.”Almost 200years later,in2004,Geim and Novosolov showed that thin transparent adhesive tape could be used to exfoliate graphite into single atomic layers of graphene and demonstrated atomical-ly thin devices(1).As a process,exfoliation of layered solids has had a transformative effect on materials science and technology by opening up properties found in the two-dimensional(2D) exfoliated forms,not necessarily seen in their bulk counterparts.Layered materials are defined as solids with strong in-plane chemical bonds but weak out-of-plane,van der Waals bonds.Such materials can be sheared parallel or expanded normal to the in-plane direction.In the extreme limit,these processes yield nanometer-thin—even atomically thin—sheets that are not at all characteristic of the bulk precursor.This production of extremely thin sheets from layered precursors is known as exfoliation or delamination,although in this work we will use the former term.The sheets produced are generally referred to as nanosheets, where“nano”refers to the magnitude of the thick-ness.Although in the ideal case such nanosheets consist of single monolayers,they are often man-ifested as incompletely exfoliated flakes compris-ing a small number(<10)of stacked monolayers.There are many types of layered materials,whichcan be grouped into diverse families(Fig.1).The simplest are the atomically thin,hexagonalsheets of graphene(1–3)and hexagonal boronnitride(h-BN)(4).Transition metal dichalco-genides(TMDs)(such as MoS2and WSe2)(5,6)and metal halides(such as PbI2and MgBr2)(7)have near-identical structures and consist ofa plane of metal atoms sandwiched betweenplanes of halide/chalcogen yered me-tal oxides(such as MnO2,MoO3,and LaNb2O7)(8–11)and layered double hydroxides(LDHs)[such as Mg6Al2(OH)16](8,12)represent a di-verse class of materials with a large variety ofstructures.Similarly,layered silicates,or clays,are minerals and exist as many different types,with well-known examples being montmorilloniteor the micas(13,14).Generally,oxides,LDH,and clay nanosheets are charged and are accom-panied by charge-balancing ions(8,14).Otherinteresting families are the layered III-VIs(suchas InSe and GaS)(15),the layered V-VIs(such asBi2Te3and Sb2Se3)(16),the metal trichalcogenides,and metal trihalides.Although many other lay-ered materials exist(Table1),all share a planar,anisotropic bonding and therefore the potentialto be exfoliated into nanosheets.One substantial advantage of layered materi-als is their diversity.Even before exfoliation,themany families of layered materials display a verybroad spectrum of properties.For example,TMDs(5,6)occur as more than40different types de-pending on the combination of chalcogen(S,Se,or Te)and transition metal(5,6).Depending onthe coordination and oxidation state of the metalatoms,or doping of the lattice,TMDs can be me-tallic,semimetallic,or semiconducting(6).In ad-dition,these materials display interesting electronicbehavior,such as superconductivity or charge-density wave effects(6).Similarly,the many dif-ferent types of layered metal oxides have interestingelectronic,electrochemical,and photonic proper-ties(8).These materials have been fabricated intotransistors,battery electrodes,and magneto-opticdevices(8–10).Thus,even as bulk crystals,lay-ered materials are an interesting and potentiallyuseful material class.This makes them an excitingstarting material for exfoliation into nanosheets.As we will see below,exfoliation dramaticallyenhances the range of properties displayed by analready diverse material type.Why Exfoliate?The simplest effect of exfoliation is to dramati-cally increase the accessible surface area of amaterial.For surface-active or catalytic materials,this can radically enhance their chemical andphysical reactivity.The ion exchange ability ofminerals such as vermiculite to purify water at1000meq/kg depends on its near106-fold increasein surface area after expansion(13).In structuralmechanics,the strength and stiffness of compositesincrease as the thickness of planar fillers,such asclay or graphite,decreases(17).When heat causesexfoliation,a layered material can be used as anintumescent(or thermally expansive)material.Hence,vermiculite and graphite are used for fireretardation in paints and firestop pillows be-cause they reduce their density upon heating andproduce an ash of low thermal conductivity.As interest in nanotechnology has intensi-fied in recent decades,another important advan-tage of exfoliation has emerged.In a layeredcrystal,the electronic wave function extendsin three dimensions.However,after exfoliationelectrons are constrained to adopt a2D wavefunction,thus modifying the electronic bandstructure.Graphite can be transformed into agraphene monolayer after exfoliation,with elec-tronic properties that differ greatly from any othermaterial(1).These include an enormously highcarrier mobility and other exciting properties,such as Klein tunnelling and the half-integer quan-tum Hall effect(1,3).Likewise,the propertiesof MoS2depend strongly on exfoliation state.The bandgap of MoS2changes on exfoliationfrom1.3eV for the bulk crystal to1.9eV foran exfoliated nanosheet.Because the bandgapchanges monotonically with number of mono-layers per nanosheet,this allows the electronicresponse to be chosen at will(18).In addition,although multilayer MoS2is not photolumines-cent,exfoliation-induced changes in its electron-ic structure lead to photoluminescent behaviorin exfoliated monolayers(19).Similar behavioris expected in other layered semiconductors(5).Large-Scale Exfoliation in Liquids?The exfoliation of graphite demonstrated by Geimand Novolosov was achieved essentially by rubbinggraphite on a surface(1).Such mechanical ex-foliation remains the source of the highest-qualitygraphene samples available and has resultedin some major advances(1).However,it suffersfrom low yield and a production rate that is not1School of Physics and Centre for Research on Adaptive Nano-structures and Nanodevices,Trinity College,Dublin,D2Dublin,Ireland.2School of Chemistry,Trinity College,Dublin,D2Dublin,Ireland.3Materials Science and Engineering,Rutgers University,Piscataway,NJ08901,USA.4Department of Chemistry,North-western University,Evanston,IL60208,USA.5Department ofChemical Engineering,Massachusetts Institute of Technology,Cambridge,MA02139,USA.*Corresponding author.E-mail:colemaj@tcd.ie SCIENCE VOL34021JUNE20131226419-1o n J u l y 3 , 2 0 1 3 w w w . s c i e n c e m a g . o r g D o w n l o a d e d f r o mtechnologically scalable in its current form.One possible solution is the exfoliation of lay-ered compounds in liquids to give large quan-tities of dispersed nanosheets.This should allow for methods to obtain sizable quantities of 2D materials that can be processed by using exist-ing industrial techniques,such as reel-to-reel manufacturing.Here,we briefly outline the four main liquid exfoliation techniques for layered materials (schematics are provided in Fig.2,and examples of exfoliated nanosheets are pro-vided in Fig.3).One of the oldest methods of exfoliating lay-ered crystals with low reductive potential is oxi-dation and subsequent dispersion into suitable solvents.The best example is that of graphite (20),in which treatment with oxidizers such as sulphuric acid and potassium permanganate results in ad-dition of hydroxyl and epoxide groups to the basal plane.The resulting hydrophillicity allows water intercalation and large-scale exfoliation to yield graphene oxide upon ultrasonication.The dispersed flakes are predominantly monolayers,typically hundreds of nanometers across,and sta-bilized against reaggregation by a negative sur-face charge at concentrations of up to 1mg/ml.Dispersed graphene oxide can be chemically re-duced in the liquid phase but will then aggregate unless surfactant or polymer stabilizers are present.Although reduction removes most of the oxides,structural defects remain,rendering the properties of oxidatively produced graphene substantially different from pristine graphene.Layered materials can also strongly adsorb guest molecules into the spacing between lay-ers,creating what are called inclusion complexes.This forms the basis of another exfoliation meth-od that is widely applied to layered materials,including graphite (21)and TMDs (22,23).Intercalation,often of ionic species,increases the layer spacing,weakening the interlayer ad-hesion and reducing the energy barrier to exfolia-tion.Intercalants such as n -butyllithium (22,23)or IBr (21)can transfer charge to the layers,re-sulting in a further reduction of interlayer bind-ing.Subsequent treatment such as thermal shock (21)or ultrasonication (22,23)in a liquid com-pletes the exfoliation process.The exfoliated nanosheets can be stabilized electrostatically by a surface charge (23)or by surfactant addition (21).In the case of MoS 2,this method tends to give highly exfoliated nanosheets (22).However,ion intercalation –based methods have drawbacks associated with their sensitivity to ambient condi-tions (22–24).Ion exchange methods take advantage of the fact that LDHs,clays,and some metal oxidesFig.1.Crystalstructures,natural-ly occurring forms,and exfoliated products for four example layered materials.(A )Graphite consists of alternating stacks of hexagonally ar-ranged carbon atoms (black spheres),(B )is a naturally occurring mineral,and (C )exfoliates to single atomic layers of carbon called graphene.(D )Vermicu-lite is a layered silicate hydrate (typ-ically Mg 1.8Fe 0.9Al 4.3SiO 10(OH)2•4(H 2O)that (E )is found naturally as a min-eral and (F )can be exfoliated,for example,upon heating.Silicon atoms are in blue,oxygen atoms are in red,Al/Mg/Fe atoms are in yellow,and interlayer counterions are in black (H and H 2O not shown).(G )MoS 2is a layered arrangement of S and Mo atoms (chalcogen atoms are in yellow,and transition metal are in green)that (H )is found naturally as the mineral molybdenite and (I )can be exfoliated to MoS 2monolayers.(J )Layered manganese dioxide (man-ganese atoms are in yellow,oxygen is in red,and interlayer counterions are in black)occurs naturally (K )as birnessite and (L )can be exfoliated to give MnO 2nanosheets.(C),(I),and (L)are adapted from (48),(87),and (58),respectively.The layer spac-ings for each material are graphite,0.35nm;vermiculite,1.5nm;MoS 2,0.6nm;and MnO 2,0.45nm.21JUNE 2013VOL 340SCIENCE1226419-2REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mTable 1.Referenced table of families of layered compounds,including structures and information on exfoliation methods,potential applications,and availablility.This table is not exhaustive.Crystal structures were obtained from the CrystalMaker Library (/library/index.html).Graphi t eTop viewSide viewF amily of layered compound StructureExfoliation methodApplicationsCommercial availabilitySonication in surfactantsolution (30, 50–53)Sonication in solvents (27, 45–48)Sonication in polymersolutions (54, 55)Graphene oxide (20,88)Many (1, 89)Widely availableMoS 2top viewMoS 2 side viewSingle-layer transistor (92)Batteries (63, 64)Top-gatephototransistors (93)Thermo-electrics (29, 58)Superconducting composites (94)Raw materials mostly available (purity issues)h-BNTop viewNitrogen BoronSide viewSonication in surfactant solution (58)Sonication in solvents (29, 56)Sonication in polymer solutions (54)Sonication in surfactant solution (58)Sonication in solvents (29, 59, 60)Sonication in polymer solutions (54)Ion intercalation (91)Composites (57)Device substrates (90)YesTransition metal ChalcogenTransition metal dichalcogenides (TMDs) SCIENCE VOL 34021JUNE 20131226419-3REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mTiTe 3top viewMnPS 3top viewTiTe 3side viewMnPS 3 side viewBatteries (96)No, only by synthesisIon intercalation (95)Wide band-gap semiconductors (97)Magnetic properties (98)No, only by synthesisIntercalation (75)Transition metal ChalcogenTransition metal Chalcogen PhosphorusTransition metal trichalcogenides (TMDs)AMo 3X 3, NbX 3, TiX 3, and TaX 3 (X = S, Se, or Te)Metal phosphorous trichalcogenides (MPX 3), such as MnPS 3, CdPS 3, NiPS 3, ZnPS 3, and Mn 0.5Fe 0.5PS 321JUNE 2013VOL 340SCIENCE 1226419-4REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mtop viewCrCl PbCl top viewMoCl CrCl 3 side viewPbCl 4 side viewNo (synthesis required)No (synthesis required)No (synthesis required)Ion intercalation (7)Polymer intercalation(99)Ion intercalation (100)Polymer intercalation (99)Ion intercalation (101)Transition metal HalideTransition metal Heavy metal Halide AmmoniumMetal halidesTransition-metal dihalides*Metal MX 3 halides, such as αRuCl 3, CrCl 3, and BiI 3†Layer-type halides with composition MX 4, MX 5, MX 6‡MoCl 2 top 2 side view3top viewHalide SCIENCE VOL 34021JUNE 20131226419-5REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mNa x (Mn 4+,Mn 3+)2O 4(birnessite) top viewNa x (Mn 4+,Mn 3+)2O 4 (birnessite) side viewVanadium oxide (V 2O 5) top viewV 2O 5 side viewSome raw materials available (purity issues)Most compounds are not availableSupercapacitors (106)Batteries (107)Catalysts (108)Dielectrics (109)Ferroelectrics (109)Ti oxidesIon intercalation (102)Mn oxidesSonication in surfactantsolution (58); Ion intercalation (103)Nb oxidesIon intercalation (104)Va oxidesPolymer intercalation (105)Transition metal Oxygen CatonVanadium OxygenOxidesTransition metal oxides : Ti oxides, Ti 0.91O 2, Ti 0.87O 2, Ti 3O 7, Ti 4O 9, Ti 5O 11; Nb oxides,Nb 3O 8, Nb 6O 17, HNb 3O 8;§ Mn oxides, MnO 2, Ti 3O 7, Na x (Mn 4+,Mn 3+)2O 421JUNE 2013VOL 340SCIENCE 1226419-6REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mMoO 3top viewMoO 3 side viewSr 2RuO 4 top viewSr 2RuO 4 side viewYesNo (only by synthesis)No (only by synthesis)Ion intercalation (110)Polymer intercalation(111)Intercalation with liquid crystals (115)Ion intercalation (protonation and ion exchange) (116)Amine surfactant (TBA +) under sonication (117)Ion intercalation (protonation and ion exchange) (114)Electrochromics (112)Light emitting diodes (113)Ferroelectrics (118)Photochromic (119)Photoluminescent (120)Layered trirutile phases HMWO (M = Nb, Ta), such as (HNbWO 6 and HTaWO 6)Hydrogen OxygenTransition metal StrontiumRutheniumOxygenOxidesTrioxides, such as MoO 3, TaO 3, and hydrated WO 3Perovskites and niobates, such as Sr 2RuO 4KCa 2Nb 3O 10, H 2W 2O 7, LaNb 2O 7, La 0.90Eu 0.05Nb 2O 7, Eu 0.56Ta 2O 7, Sr 2RuO 4, Sr 3Ru 2O 7, SrTa 2O 7, Bi 2SrTa 2O 9, Ca 2Nb 3O 10, Sr 2Nb 3O 10, NaCaTa 3O 10, CaLaNb 2TiO 10, La 2Ti 2NbO 10, and Ba 5Ta 4O15 SCIENCE VOL 34021JUNE 20131226419-7REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mTi 2Sb 2O top viewTi 2Sb 2O side viewFeOCl top viewFeOCl side viewNo (only by synthesis)No (only by synthesis)To our knowledge, these have never been exfoliatedIon intercalation (122)Superconductivity (121)Magnetic properties (121)Catalyst (redox properties) (121)Batteries (121)Batteries (123)Transition metal Pnictide CationTransition metal Halide OxygenOxidesOxychalcogenides and oxypnictides: Oxychalcogenides, LaOCuCh(Ch, chalcogenide) and derivatives, Sr 2MO 2Cu 2-δS 2 (M = Mn, Co, Ni),Sr 2MnO 2Cu 2m -0.5S m +1 (m = 1-3), Sr 4Mn 3O 7.5Cu 2Ch 2 (Ch=S, Se); oxypnictides, LaOFeAs II Oxyhalides of transition metals, such as VOCl, CrOCl, FeOCl, NbO 2F, WO 2Cl 2, and FeMoO 4Cl 21JUNE 2013VOL 340SCIENCE 1226419-8REVIEWo n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mLayered ␣ and ␥ zirconiumphosphates and phosphonatesGaSe top viewGaSe side viewCaHPO 4 top viewCaHPO 4 side viewSome available (maybe purity issues), mostly synthesizedNo (only by synthesis)Ion intercalation (124)Surfactant (125)Nonlinear optical properties, poor thermal conductivity (126)Intercalation (127)Exfoliation in water/acetone mixtures (128)Drug delivery (127)Semiconductor for dye sensitized solar cells (129)S/Se/Te Ga/InOxygen Phosphorus Cation WaterIII–VI layered semiconductorGaX (X = S, Se, Te); InX (X = S, Se Te)¶α-M IV phosphates, α-M IV (O 3P–OH)2·H 2O; and α-Metal IV phosphonates, M IV (O 3P–R)2·n H 2O# o n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o mVermiculite top viewVermiculiteside viewKaolite top viewKaolite side viewNatural minerals,available on themarket Dispersion in water(13)Intercalation (130)Polymer intercalation(131)Catalysis (130)Composites (131)Lightweightnanocomposites forstructural applications(132)Clay-dye complexesand photoactivematerials (131)Organoclays as ionicand electronicconductors (compositeswith conductivepolymers) (131)Thermal and barrierpropertiesnanocomposites (133)Aluminum Oxygen Silicon OH-Oxygen Silicon Cation Intercalates/-C/-OHClays(layered silicates)2:1 Layered silicates**:Smectites, M n+x/n.yH2O[Al4-xMgx](Si8)O20(OH)4;talc, [(Mg3)(Si2O5)2(OH)2];vermiculite, [Mg6.Si6Al2/O20(OH)4] [M n+1/n] (Mg6);biotite [(MgFe)3(Si3Al)O10(OH)2]K;phlogopite, [(Mg6)(Si6Al2)O20(OH)4]Ba;fluorphlogopite, [Mg11/4(Si6Al2)O20F4][(M2+)3/2;margarite, [(Al2)(Si2Al2)O10(OH)2]Ca;and muscovite, [(Al2)(Si3Al)O10(OH)2]K1:1 Layered Silicates ††: Kaolite,[Al4Si4O10](OH)8; halloysite,Al4Si4O10(OH)8.4H2OonJuly3,213www.sciencemag.orgDownloadedfromBrucite (Mg 2+x , Mg 3+x (OH)2 (A n–)x/n . yH 2O)top viewBrucite (Mg 2+x , Mg 3+x (OH)2 (A n–)x/n . yH 2O) side viewTi3C2No, only bysynthesisYesIntercalation (134)Surfactant-assistedexfoliation and intercalation ofmolecules (135)Surfactant exfoliation (136)Solvent exfoliation in DMF (137)Functionalizationfollowed by exfoliation in solvents (138)Biocompatible–bio-hybrids/drug delivery (12, 134)Bionanocomposites with functional and structural properties (139)Extra oxygen and hydrogen at layers surface are present as a consequence of the exfoliation treatment with HF (66, 67).Batteries andsupercapacitors (140)Carbon TitaniumOxygenHydrogenCationLayered double hydroxides (LDHs)Ternary transition metal carbides and nitridesGeneral formula: M(II)1–x M(III)x (OH)2(A n –)x /n . yH 2O, where M(II) = divalent cation; M(III) = trivalent cation; A = interlayer anion; and n – = charge on interlayer anion‡‡Derivatives from MAX phases, where M = transition metal; A = Al or Si;and X=C or N§§Oxygen Hydrogen*These are iso-structural with TMDs.†These are defect CdI2structure types.‡These are heavy metal halides (perovskite type)structurally similar to transition metal dihalides withorganic ammonium interlayers.§Protons emplaced between 2D of Nb 3O 8–anion nanosheets composed of NbO 6octahedra.‖They contain oxide layers separated by distinct layers,which contain the softer chalcogenide (S,Se,and Te)or pnictide (P,As,Sb,and Bi).¶The building block has a trigonal structure,consisting of a pair of (M 3X 3)rings linked by M –M yers interact through van der Waals forces between the X outermost planes.#R is an organic radical,and n is the number of water molecules that can be intercalated in the interlayer region.**The 2:1notation means that the layers consist of two tetrahedral silicate sheets sandwiching one octahedral sheet.††Layer consists of one tetrahedral silicate sheets and one octahedral sheet.‡‡The structure of LDHs can be described by considering Mg(OH)2,which consists of Mg 2+ions coordinated octahedrally by hydroxyl groups.The octahedral units share edges to form infinite,charge neutral layers.In an LDH,isomorphous replacement of a fraction of the Mg 2+ions with a trivalent cation,such as Al 3+,occurs and generates a positive charge on the layers that necessitates the presence of interlayer,charge-balancing,anions.The remaining free space of the interlayer is occupied by water of crystallization.§§Layered M 2X,M 3X 2,M 4X 3,where M =transition metal and X =C or N,can be obtained after removal of the A layer with hydrofluoric acid (HF).o n J u l y 3, 2013w w w .s c i e n c e m a g .o r g D o w n l o a d e d f r o m。

Layered double hydroxide nanosheets via solvothermal delamination

1. Introduction
Layered double hydroxides (LDHs) are a family of host-guest
type anionic clays w让h the general formula [Mz+1_xM，3+x(OH)2la+ (Xn-a/n) ^H20, where usually z = 2, M2+ and M，3+ can be most di
phous substitution of M2+ cations by M，3+ cations in the octahe
dral sites results in a net positive charge of the hydroxide layers, which is balanced by anions in the interlayer space [5].
ABSTRACT
A new solvothermal post-synthesis treatment for preparing high aspect ratio magnesium aluminium lay ered double hydroxides (MgAI-LDHs) has been developed. Treating laurate-intercalated MgAl-LDHs in pure ethanol in an autoclave for 48 h at 150 °C was found to produce delaminated MgAl-LDH nanosheets with a thickness of 〜2.6nm and an aspect ratio of 〜105. It is proposed that the high pressure solvother

Ag_掺杂NiFe_层状双氢氧化物应用于电催化析氢研究　

第42卷第8期2023年8月硅㊀酸㊀盐㊀通㊀报BULLETIN OF THE CHINESE CERAMIC SOCIETY Vol.42㊀No.8August,2023Ag 掺杂NiFe 层状双氢氧化物应用于电催化析氢研究孙冠军,李建保,王㊀敏,陈拥军,骆丽杰(海南大学材料科学与工程学院,南海海洋资源利用国家重点实验室,海口㊀570228)摘要:开发廉价高效的催化剂是发展电解水产业的关键㊂层状双氢氧化物(LDH)在电催化析氧反应中表现出优异的性能,但这类催化剂在析氢反应中表现出的电化学性能并不好㊂本文通过将Ag 元素掺杂在NiFe-LDH 纳米片阵列中,获得了优异的析氢性能㊂结果表明,在1mol /L KOH 溶液中,电流密度达到10mA㊃cm -2所需的过电位仅为73mV,且塔菲尔斜率为61.3mV㊃dacade -1㊂在800mA㊃cm -2的大电流密度下过电位仅为493mV,明显低于商用铂碳催化剂㊂在长达30h 稳定性测试后仍保持90%以上电化学性能㊂催化性能的改善归因于Ag 掺杂NiFe-LDH使纳米片尺寸减小和比表面积增加,有效提升产氢动力学并改善电子传输,从而优化NiFe-LDH 的电催化析氢性能㊂关键词:层状双氢氧化物;镍铁;银;掺杂;电催化;析氢反应中图分类号:O643.36㊀㊀文献标志码:A ㊀㊀文章编号:1001-1625(2023)08-2960-08Application of Ag Doped NiFe Layered Double Hydroxides in Electrocatalytic Hydrogen EvolutionSUN Guanjun ,LI Jianbao ,WANG Min ,CHEN Yongjun ,LUO Lijie(State Key Laboratory of Marine Resource Utilization in South China Sea,School of Materials Science and Engineering,Hainan University,Haikou 570228,China)Abstract :Developing cheap and efficient catalysts is the key to develop electrolytic water yered double hydroxides (LDH)exhibit excellent performance in electrocatalytic oxygen evolution reactions,but these catalysts exhibit poor electrochemical performance in hydrogen evolution reactions.Excellent hydrogen evolution performance was achieved by doping Ag element into NiFe-LDH nanosheet arrays.The results show that in 1mol /L KOH solution,the required overpotential for a current density of 10mA㊃cm -2is only 73mV,and the Tafel slope is 61.3mV㊃dacade -1.At a high current density of 800mA㊃cm -2,the overpotential is only 493mV,which is significantly lower than that of commercial platinum carbon catalysts.After 30h of stability testing,the electrochemical performance remains above 90%.The improvement in catalytic performance is attributed to the reduction in nanosheet size and increase in specific surface area caused by Ag doping with NiFe-LDH,which effectively enhances hydrogen production kinetics and improves electron transport,thereby optimizing the electrocatalytic hydrogen evolution performance of NiFe-LDH.Key words :layered double hydroxide;NiFe;Ag;doping;electrocatalysis;hydrogen evolution reaction收稿日期:2023-03-27;修订日期:2023-04-25基金项目:国家自然科学基金(52172086)作者简介:孙冠军(1998 ),男,硕士研究生㊂主要从事电催化分解水制氢的研究㊂E-mail:875546550@通信作者:李建保,博士,教授㊂E-mail:ljb_555@ 0㊀引㊀言随着科技的飞速发展,人类社会对于能源的消耗日益加剧,传统化石能源的大量使用不仅造成了严重的环境污染,还带来了愈加严峻的能源短缺问题[1-2]㊂新型可再生能源因易制备㊁清洁无污染等优点而在新能源汽车㊁风能发电机等诸多领域取代化石能源成为最优选择㊂其中,氢能因具有高能量密度和零污染等优点㊀第8期孙冠军等:Ag掺杂NiFe层状双氢氧化物应用于电催化析氢研究2961而备受关注㊂目前获取氢气的主要途径包括煤炭气化和甲烷-水蒸气重整[3-4],这些方法制备出的氢气不仅含有许多杂质气体,并且反应过程中还伴随着大量化石能源的消耗,这背离了我们发展氢能的初衷㊂近年来,利用高性能电催化剂进行电化学水分解制氢因具有成本低廉㊁绿色无污染等优点,使用范围逐渐扩大[5]㊂为提高水分解效率和降低能耗,研究者们已经进行过许多尝试,探索了诸多价格低㊁储量大的元素用作析氧反应(oxygen evolution reaction,OER)电催化剂,特别是Fe/Co[6]/Ni及其相应的氧化物[7-8]㊁氢氧化物[9]㊁硫化物[10]㊁硒化物㊁氮化物等[11-12],廉价易得,适合大规模使用㊂其中镍铁层状双氢氧化物(NiFe-layered double hydroxides,NiFe-LDH)的OER性能明显优于其他非贵金属催化剂,但其析氢反应(hydrogen evolution reaction,HER)活性在碱性溶液中极差(在10mA㊃cm-2下的超电势大于210mV)[13]㊂通常在碱性条件下,电催化剂的HER活性主要由水解离过程(Volmer步骤)决定[14-16]㊂据报道,贵金属掺杂是提高电催化剂催化活性的有效策略㊂Luo等将Ru原子掺入NiFe-LDH从而有效地降低Volmer反应势垒,NiFeRu-LDH达到10mA㊃cm-2的电流密度所需电压仅为1.52V,这远低于Pt/C-Ir/C的全解水电压[15]㊂Ye等通过在CoFe层状双氢氧化物中掺杂Rh,将析氢反应过电位降低至28mV(电流密度10mA㊃cm-2),这归因于Rh掺杂引入的Fe空位和中空结构可以优化HER动力学[17]㊂除直接掺杂外,通过其他改性方式同样可以显著提高催化活性㊂Ma等通过电蚀刻法在泡沫镍基底上生长出Ag@NiFe分层结构,在180mA㊃cm-2电流密度下HER和OER过电位分别是10和80mV[18]㊂Cheng等通过磁场辅助化学沉积法在NiFe合金纳米线表面上制备出超薄和非晶态NiFe氢氧化物,显著提高了电荷和质量(反应物和氧气气泡)的转移效率,在碱性环境中,500和1000mA㊃cm-2电流密度下OER所需过电位仅为120和248mV,稳定性长达258h[19]㊂在众多贵金属中,Ag因具备价格低廉㊁高导电性和调控电子结构并改善吸附性等优点而被选为掺杂剂材料[20-23],但是目前学界对于Ag掺杂NiFe-LDH的电催化析氢性能进行的探究较少㊂本文通过水热法将Ag掺杂在NiFe-LDH纳米片阵列中,通过XRD㊁XPS㊁SEM及电化学测试手段研究了Ag掺杂后NiFe-LDH的物相㊁形貌及电化学性能,为Ag掺杂NiFe层状双氢氧化物应用于电催化析氢提供了重要实验基础㊂1㊀实㊀验1.1㊀原材料及制备过程取3cmˑ3cm大小的泡沫镍,用5%(质量分数)的稀盐酸超声清洗25min去除表面氧化物,随后用去离子水和酒精依次超声清洗15min去除泡沫镍中残留的酸和盐,烘干后作为基底材料㊂称量0.1870g(0.75mmol) Ni(CH3COO)2㊃4H2O,0.1010g(0.25mmol)Fe(NO3)3㊃9H2O,0㊁0.0017㊁0.0119和0.0340g(0㊁0.01㊁0.07和0.20mmol)AgNO3,0.1500g(2.50mmol)CO(NH2)2后将药品混合溶解在20mL去离子水中,搅拌得到均匀的溶液,将溶液和泡沫镍转移至50mL的特氟龙内衬不锈钢制高压反应釜中,置入120ħ烘箱中加热12h后随炉冷却至室温㊂将泡沫镍取出,分别用去离子水和无水乙醇超声清洗10min去除表面的盐和部分产物,随后在55ħ的真空干燥箱中干燥5h,得到最终产物㊂将Ag掺杂量为0.07mmol的样品命名为NiFeAg-LDH㊂1.2㊀表征和性能测试采用X射线衍射仪(XRD,D8Advanced)对所得样品结构及成分进行分析,测试条件为Cu靶,扫描范围为5ʎ~50ʎ㊂通过扫描电子显微镜(SEM,s-4800)和透射电子显微镜(TEM,jem-2100f)观察材料的微观形貌和晶面间距㊂1.3㊀电极制备室温下使用三电极体系电化学单池,将负载NiFeAg-LDH和NiFe-LDH的泡沫镍切成3mmˑ3mm的工作电极㊂以标准饱和甘汞电极作为参比电极,碳棒作为对电极㊂并以商用催化剂Pt/C(20%)与Nafion混合均匀后滴于3mmˑ3mm泡沫镍上,负载量为2mg㊃cm-2㊂1.4㊀电化学产氢(HER)通过CHI760E电化学工作站测试电催化活性,向1mol/L KOH中通氮气30min后进行HER测试㊂循2962㊀新型功能材料硅酸盐通报㊀㊀㊀㊀㊀㊀第42卷环伏安法(cyclic voltammetry,CV)电压测试范围为-0.9~1.8V,扫描速率为50mV㊃s -1,得到稳定的CV 曲线后以5mV㊃s -1的扫描速率进行线性扫描伏安法((linear sweep voltammetry,LSV)测试,获得性能曲线㊂电化学阻抗(electrochemical impedance spectroscopy,EIS)测试初始电压为-0.124V,测试频率为0.1Hz ~100kHz㊂通过恒电流测试(chronopotentiometry,CP)测得稳定性,电压范围为0~2V,观察曲线变化获得稳定性图谱㊂2㊀结果与讨论图1㊀NiFe-LDH 和NiFeAg-LDH 样品的XRD 谱Fig.1㊀XRD patterns of NiFe-LDH and NiFeAg-LDH samples2.1㊀催化剂的表征NiFe-LDH 和NiFeAg-LDH 材料的XRD 谱如图1所示㊂从图1中可以看出,NiFe-LDH (JCPDS #40-0215)相在2θ=11.410ʎ㊁22.974ʎ和34.425ʎ处有3个最强峰,分别代表LDH 的(003)㊁(006)和(012)晶面㊂当Ag 元素掺杂NiFe-LDH 后,NiFeAg-LDH 的(003)㊁(006)和(012)晶面具有清晰衍射峰,且相较于未掺杂的NiFe-LDH,NiFeAg-LDH 各峰位相对强度明显增强,38.992ʎ㊁45.985ʎ处的两个较弱峰在NiFe-LDH 中未明显显现,仅在掺杂后的NiFeAg-LDH 中有明显峰位,这说明Ag 原子已成功掺入NiFe-LDH 材料中,未发生相分离,并且提高了产物结晶度,这可能成为提高催化活性的影响因素之一㊂为探究Ag 元素的实际掺杂比例及样品内部Ag 元素的存在方式㊂对NiFeAg-LDH 样品进行XPS 表征,结果如图2所示㊂对Fe㊁Ni㊁Ag 各元素峰面积进行对比分析,发现在NiFeAg-LDH 样品中Fe㊁Ni㊁Ag 摩尔比为68ʒ25ʒ7,这与原料中添加元素的摩尔比一致,同时对不同含量Ag 掺杂后NiFeAg-LDH 样品进行EDS 测试,结果如图3所示,可以看出各产物中元素比例与原料中所添加比例近似保持一致,证明Ag 通过掺杂方式进入产物㊂从Ag 元素3d 轨道XPS 谱可以看出,367.8和373.8eV 处存在两个明显峰位,通过文献对比可知,这两个峰位分别对应Ag +的3d 3/2和3d 5/2轨道[24],Ag 在NiFeAg-LDH 样品中以正一价离子态存在㊂Ag 掺杂前后NiFe-LDH 样品的SEM 照片如图4所示㊂可以看出较少量的Ag 掺杂并未改变样品微观结构,NiFe-LDH(0mmol Ag)㊁NiFeAg-LDH(0.01mmol Ag)和NiFeAg-LDH(0.07mmol Ag)样品的形貌均为纳米片㊂但掺杂Ag 之后,形成的纳米片结构明显具有更完整的片状结构以及更高的分离度,在尺寸无明显改变的情况下,这可能使纳米片具有更大的比表面积,对改善电催化性能有所帮助㊂但当过量Ag(0.20mmol)掺杂后,产物中纳米片结构明显被破坏,并发生团聚现象,这可能导致电催化性能降低㊂第8期孙冠军等:Ag 掺杂NiFe 层状双氢氧化物应用于电催化析氢研究2963㊀图2㊀NiFeAg-LDH 样品的XPS 谱Fig.2㊀XPS spectra of NiFeAg-LDHsamples 图3㊀样品的EDS 能谱Fig.3㊀EDS spectra ofsamples 图4㊀样品的SEM 照片Fig.4㊀SEM images of samples2964㊀新型功能材料硅酸盐通报㊀㊀㊀㊀㊀㊀第42卷㊀㊀为了探明有关NiFeAg-LDH 的详细结构信息,利用透射电子显微镜(TEM)对NiFeAg-LDH 微观形貌和晶面间距进行表征(见图5)㊂如图5(a)所示,可以看到NiFeAg-LDH 样品为清晰均匀的纳米片结构,且分离度良好㊂图5(b)为样品的高倍透射图像,可以得出晶面间距为0.25nm,对应NiFeAg-LDH 的(012)晶面㊂这也进一步说明Ag 掺杂没有改变LDH 的微观特性㊂图5㊀NiFeAg-LDH 样品的微观形貌Fig.5㊀Microscopic morphology of NiFeAg-LDH samples 2.2㊀电催化析氢性能研究在室温下使用标准三电极体系在氮气饱和的1mol /L KOH 溶液中进行电化学测试㊂将原位生长在泡沫镍基底上的催化剂材料裁切成0.3cm ˑ0.3cm 大小并用作工作电极,碳棒为对电极,选用饱和甘汞电极(Hg /HgCl /KCl)为参比电极,电催化测试数据中电位均为相对于可逆氢电极(reversible hydrogen electrode,RHE)的电位E (RHE)=[E (SCE)+0.059pH +0.240]V㊂为探究Ag 掺杂后对NiFe-LDH 电化学性能的影响及最佳Ag 掺杂比例,对NiFe-LDH 和不同比例Ag 掺杂后的NiFe-LDH 进行线性伏安法(linear sweep voltammetry,LSV)测试以表征其HER 性能,结果如图6(a)所示㊂选取电流密度为10mA㊃cm -2时的过电位作为标准,各样品性能如图6(b)所示,可以看出,掺杂Ag 后明显降低了催化反应所需过电位,并且随着Ag 掺杂量逐渐增加,过电位不断降低,在掺杂量为0.07mmol 时获得最低过电位,继续增加Ag 掺杂量反而导致过电位升高㊂可能是由于Ag 掺杂量过少时导致活性位点不足,因此增加Ag 掺杂量可增加活性位点数量,提高催化性能,过量Ag 的引入导致结构被破坏,催化性能降低㊂各样品电化学阻抗测试结果如图6(c)所示,Zᶄ为阻抗实部,Zᵡ为阻抗虚部,可以看出,在Ag 掺杂量为0.07mmol 时,样品具有最低的传质电阻,更有利于电极与电解质之间电荷的转移㊂图6㊀在N 2饱和的1mol /L KOH 溶液中各样品的电化学性能Fig.6㊀Electrochemical performance of each sample in 1mol /L KOH solution saturated with N 2为进一步探究NiFeAg-LDH 材料的催化性能,以泡沫镍和商用铂碳为对比样,在同样条件下测试碱性HER 性能,并与主样品性能进行对比㊂图7为在N 2饱和的1mol /L KOH 溶液中主样品与其他催化剂的电第8期孙冠军等:Ag 掺杂NiFe 层状双氢氧化物应用于电催化析氢研究2965㊀化学性能㊂如图7(a)所示的LSV 曲线,NiFeAg-LDH 的性能明显优于泡沫镍和NiFe-LDH,仅次于Pt /C,在10mA㊃cm -2电流密度下过电势为73mV,而在相同电流密度下Pt /C㊁NiFe-LDH 和泡沫镍的过电势分别为45㊁255和324mV(图7(b))㊂而在较大电流密度下,NiFeAg-LDH 样品的过电位甚至要低于Pt /C 催化剂,从LSV 曲线所示趋势来看,随着电流的继续增大,二者的差距还在不断拉开㊂实际上,大电流密度下的过电位更具有实用意义,NiFeAg-LDH 样品在大电流密度下的过电位性能优异,因此其在商业化碱性电解水市场中有着巨大的应用潜力㊂为进一步分析各催化剂的析氢动力学,通过对LSV 曲线进行拟合得到NiFeAg-LDH㊁NiFe-LDH㊁泡沫镍和商用Pt /C 的Tafel 斜率,分别为61.3㊁179.1㊁259.9和37.2mV㊃decade -1(如图7(c)所示),这表明NiFeAg-LDH 具有远高于未掺杂样品NiFe-LDH 和泡沫镍的析氢动力学,仅次于Pt /C㊂图7(d)为各样品的电化学阻抗图谱R s 为溶液内阻,R ct 为电荷转移电阻,CPE 代表常相位角元件,可以看出,NiFeAg-LDH 的R ct 远小于纯NiFe-LDH 和泡沫镍的电荷转移电阻,表明与NiFe-LDH 和泡沫镍相比,NiFeAg-LDH 电极和电解质之间的电子转移速率更大,可与Pt /C 催化剂的电子转移速率相媲美㊂综上所述,通过与未掺杂NiFe-LDH㊁泡沫镍和商用Pt /C 进行对比,发现NiFeAg-LDH 具有非常优秀的电催化性能,具有替代甚至超越Pt /C 催化剂的潜力㊂图7㊀在N 2饱和的1mol /L KOH 溶液中主样品与其他催化剂的电化学性能Fig.7㊀Electrochemical performance of main sample and other catalysts in 1mol /L KOH solution saturated with N 2为进一步说明NiFeAg-LDH 样品的催化性能,将其与文献中报道的其他电催化剂进行对比,结果如表1所示㊂可以看出,相较于其他NiFe-LDH 基以及非贵金属基电催化材料而言,本文制备的样品性能较为优越,本文中所做工作也可为相关研究提供参考,为进一步提高NiFe-LDH 基电催化剂性能提供新的思路㊂除以上基础电化学测试外,电催化析氢的稳定性也是衡量性能的一个重要指标,仅能在实验室中表现出短暂高催化活性的材料不具备实际应用价值㊂因此我们通过恒电流法对掺杂Ag 元素的样品进行了稳定性测试,如图8所示,在长达30h 以上的稳定性测试后样品仍旧保持90%以上的电流密度,这说明在该催化剂在10mA㊃cm -2的电流下具有比较优异的稳定性㊂同时对稳定性测试后样品的微观形貌进行表征,以验证2966㊀新型功能材料硅酸盐通报㊀㊀㊀㊀㊀㊀第42卷稳定性测试结果㊂图9为30h 稳定性测试后样品的SEM 照片,可以看出,反应前后样品的整体形貌并未发生明显变化,证明NiFeAg-LDH 在HER 反应后,依然保持原来的纳米片形貌,进一步印证材料具有优良稳定性㊂表1㊀NiFeAg-LDH 与已报道电催化剂在1mol /L KOH 溶液中电催化HER 性能的对比Table 1㊀Comparison of electrocatalytic HER performance between NiFeAg-LDHand reported electrocatalysts in 1mol /L KOH solutionCatalyst Overpotential /mV Tafel slope /(mV㊃decade -1)Reference NiFeAg-LDH7361.3This work 20%Pt /C 4537.2This work NiFe-LDH /NF21058.9[12]NiFeO x /CFP 88118[25]NiFe-LDH NS /DG10300210[26]图8㊀NiFeAg-LDH 在电流密度为10mA㊃cm -2处的长期HER 稳定性测试曲线Fig.8㊀Long-term HER stability test curve of NiFeAg-LDH at a current density of 10mA㊃cm -2图9㊀30h HER 稳定性测试后的NiFeAg-LDH 的SEM 照片Fig.9㊀SEM image of NiFeAg-LDH after 30h HER stability test 3㊀结㊀论1)Ag 掺杂的NiFe-LDH 在10mA ㊃cm -2电流密度下碱性析氢过电位仅为73mV,塔菲尔斜率为61.3mV㊃decade -1㊂在500和800mA㊃cm -2的大电流密度下碱性析氢过电位仅为387和493mV,明显低于Pt /C,并在30h 以上稳定性测试后,仍旧保持90%以上的电流密度㊂2)优异的催化性能归因于Ag 掺杂NiFe-LDH 后有效提升了材料的产氢动力学并改善了电子传输㊂参考文献[1]㊀BARNHAM K W J,MAZZER M,CLIVE B.Resolving the energy crisis:nuclear or photovoltaics?[J].Nature Materials,2006,5(3):161-164.[2]㊀ROEMMICH D,CHURCH J,GILSON J,et al.Unabated planetary warming and its ocean structure since 2006[J].Nature Climate Change,2015,5(3):240-245.[3]㊀ZOU X X,ZHANG 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nanoclusters relaycatalysis with multi-active sites for efficient alkaline hydrogen evolution reaction[J].Applied Catalysis B:Environmental,2023,325:122316.[9]㊀SARI F N I,TRAN N T T,LIN Y X,et al.Electronic structure modification induced electrochemical performance enhancement of bi-functionalmulti-metal hydroxide[J].Electrochimica Acta,2023,439:141616.[10]㊀DENG S J,LIU C S,ZHANG Y,et rge-scale preparation of ultrathin bimetallic nickel iron sulfides branch nanoflake arrays for enhancedhydrogen evolution reaction[J].Catalysts,2023,13(1):174.[11]㊀AL-NAGGAR A H,SHINDE N M,KIM J S,et al.Water splitting performance of metal and non-metal-doped transition metal oxideelectrocatalysts[J].Coordination Chemistry Reviews,2023,474:214864.[12]㊀MA Y F,CHEN W H,JIANG Z Q,et al.NiFe nanoparticles supported on N-doped graphene hollow spheres entangled with self-grown N-dopedcarbon nanotubes for liquid electrolyte/flexible all-solid-state rechargeable zinc-air batteries[J].Journal of Materials 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石墨烯增强铜基复合材料的性能研究

Value Engineering0引言随着科学技术不断发展，对铜的性能需求也不断提高。

例如：对铜的导电导热性能、机械性能、耐磨性能以及耐腐蚀等。

目前，第二相掺杂是提高铜基体材料性能最有效的方法之一，通常可分为金属类掺杂和碳类掺杂。

金属元素掺杂虽然能提高铜基体的机械性能和耐磨性能，但导电和导热性能会大幅度降低[1]；碳纤维（CNFs ）作为增强相制备的复合材料虽然在导电、导热和耐磨性方面表现优异，但由于铜基体和CNFs 界面润湿性差使机械性能显著下降；掺入碳纳米管（CNTs ）使铜基体各方面性能都优于CNFs ，但CNTs 制备困难、价格昂贵而且不易在铜基体中均匀并有序的分散[2]。

相比之下，石墨烯由于特殊的二维结构，在导电、导热以及力学性能方面表现非常优异，并且制备难度相对CNTs 较低，因此将石墨烯作为铜基体材料的增强相十分合适[3]。

本实验通过掺杂不同含量的石墨烯，研究了不同石墨烯含量对铜基体的机械性能、导热性能和导电性能的影响。

1实验部分1.1实验原材料聚酰亚胺（PI ）膜；无水乙醇（EtOH ）；5~10μm 铜粉。

1.2实验制备与表征仪器激光雕刻机（SK-F30）、磁力搅拌台（RCT ）；水浴超声机（KH -3200DE ）；离心机（AVANTIJ -15）；真空干燥箱（DZF-6020）；等离子放电烧结炉（FCT ）。

扫描电子显微镜（JSM-6610）；多功能力学性能实验机（Instron 9657）；激光热导仪（LFA457）；多功能数字式四探针测试仪（ST-2258C ）。

1.3实验流程实验流程主要是[4，5]：①石墨烯的制备。

激光以6W 的功率刻蚀PI 膜制备石墨烯，随后将PI 膜上表面的石墨烯剥落并研磨。

②湿法粉末混合阶段。

在装有50ml 无水乙醇、10g 铜粉末的烧杯里分别加入0g 、0.05g 、0.1g 、0.15g 和0.2g 的石墨烯粉末并且搅拌均匀。

为了使粉末状的铜和石墨烯更加充分的分散于乙醇溶液中，将铜和石墨烯的粉末混合悬浊液持续超声1小时改善分散性。

磁性纳米颗粒研究热点

磁性纳米颗粒研究热点近年来,磁性纳米颗粒因为其优异的物理化学性质，如良好的磁性能，大的比表面积，表面易于功能化而被广泛地应用于各个领域。

主要为催化剂[1],吸波材料[2],生物医学工程[3],数据存储等。

磁性纳米颗粒在催化剂方面体现出极大的优势.通过将磁性纳米颗粒作为核,再将表面包覆不同的材料，如氧化硅，碳，聚合物等构建核壳纳米颗粒,能发展出一种新型催化剂.壳层材料提供催化活性，磁核协同催化。

既能提高催化效率，同时在外加磁场对磁性核作用下可以对催化剂进行分离和控制.这样就能够实现磁性纳米颗粒的可磁性回收和重复使用[4]。

如Xuan[5]等通过制备Fe3O4/Polyaniline/Au大幅提高了催化剂的可循环利用次数,从而方便的实现将催化剂控制和回收，将催化剂的循环利用,因此也降低了成本。

中科院的Huang和Liu[6]等合成的具有高比表面Ag的Fe3O4@TiO2纳米复合材料在半小时内可以完全催化降解亚甲基蓝溶液，由于具有磁性,所以通过外磁场分离后可以重复使用，并且重复使用光催化效率不会降低。

目前通过对磁性纳米颗粒进行表面改性或修饰，或者壳核结构设计，以合成出一系列的催化剂，并成功应用于有机合成中。

提高磁性纳米催化剂的稳定性和分散性是研究重点。

使用低毒性且易得的前体、环境友好溶剂和载体，在温和条件下合成稳定性好、活性高的超顺磁性纳米催化剂，将是今后磁性纳米催化剂发展方向[7]。

随着电子技术的飞速发展,人们日常生活中受到的电磁辐射不断增多,同时为适应现代战争的需要,隐身材料在武器中将被广泛应用,因此,吸波材料的研究具有重要的实用价值。

磁性吸波材料是目前研究和应用最多的一类[8]。

将类似铁氧体的纳米磁性材料放入涂料中，能够使涂料既有优良的吸波特性，又有良好的吸收和耗散红外线性能。

铁氧体系列吸波材料具有吸收率高、涂层薄和频带宽等优点。

铁氧体按晶体结构的不同，可分为立方晶系尖晶石型( AFe2O4，A 代表Mn，Zn，Ni，Mg 等) 、稀土石榴石型( Ln3Fe5O12，Ln 代表Y，Sm，Eu，Gd，Tb，Dy，Ho，Er，Tm，Lu 等) 和六角晶系磁铅石型( AFe12O19 ，A 代表Ba，Sr，Ca 等) 三种。

层状双金属氢氧化物形成机理的研究现状

CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2018年第37卷第1期·128·化工进展层状双金属氢氧化物形成机理的研究现状张胜寒，陈玉强，姜亚青，孙晨皓（华北电力大学(保定)环境科学与工程系，河北保定071000）摘要：近年来，层状双金属氢氧化物（LDH ）凭借特殊的层状结构、极强的可调控性能、优异的环境兼容性及显著的应用效果等特点，在环保、催化、储能、传感等领域得到广泛关注。

国内外多数研究集中于LDH 可控合成工艺的改进完善及LDH 的应用探索，但迄今对制备LDH 时涉及其组成结构形貌的变化过程，即其形成机理的关注较少，相关机制解释模糊，深入研究其形成过程对于可控制备具有独特形貌和特定组成的LDH 及开发更深层次的应用具有至关重要的作用。

本文介绍了LDH 层板形成机理的3个主要研究方向，即以二价金属氢氧化物的存在为基础、以三价金属氢氧化物的存在为基础和拓扑相变机制，并分别进行了阐述辨析及对比分析，发现LDH 层板的形成是一个极其复杂的过程，多种机制往往共同作用，总结认为固液及液液反应在初期成核阶段占据主导地位，各自作用程度及不同层板构筑机制产生的主导作用易受到外界环境因素影响，而更为普遍的LDH 形成机制解释需要归纳总结更多LDH 层板构筑的区别和规律，宏观和微观上探索形成过程的内在机理及科学本质，以期为LDH 开发拓展提供理论基础。

关键词：层状双金属氢氧化物；形成机理；氢氧化物；拓扑相变；化学反应中图分类号：TQ13; O611.64 文献标志码：A 文章编号：1000–6613（2018）01–0128–12 DOI ：10.16085/j.issn.1000-6613.2017-0779R esearch progress of layered double hydroxide formation mechanismsZHANG Shenghan ，CHEN Yuqiang ，JIANG Yaqing ，SUN Chenhao（Department of Environment Science and Engineering ，North China Electric Power University ，Baoding 071000，Hebei ，China ）Abstract ：Layered double hydroxide （LDH ）are a kind of promising special multifunctional layeredmaterials ，which have the excellent regulatable capability ，perfect environmental compatibility and remarkable efficiency ，so they have been studied extensively in environmental protection ，catalysis ，energy storage ，transducer and other fields. Most researches are conducted on the improvement of tailored synthesis methods and application of LDH ，whereas the research on the transformation of LDH （composition ，structure and morphology ）is rare ，especially on the general formation mechanism of LDH. The controllable preparation and in-depth applications of LDH with unique morphology and specific composition are highly demanded. An overview and comparison are presented on the interpretations of primary LDH laminate formation mechanisms which are the existence of divalent metal hydroxide ，the existence of trivalent metal hydroxides and the direct topological phase transition mechanism. The solid-liquid and liquid-liquid reactions are thought to play a dominant role in the initial nucleation stage ，while the multiple mechanisms ，the various influences and the mastery reaction are easily affected by the external conditions. To obtain a more universal mechanistic insight on LDH究方向为金属腐蚀与防护及废水处理。

CurriculumVitae

Curriculum VitaeProfessor Li Mao Guo, Ph.D. College of Chemistry and Materials Science, Anhui Normal University Beijing East Road No.1, Wuhu 241000, ChinaTel.: +86 553 3869302; Fax: +86 553 3869303E-mail: ******************Full Professor of Analytical ChemistryB.S., Anhui Normal University, China (1997)M.S., Anhui Normal University, China (2002)Ph. D., Anhui Normal University, China (2008)Research Fellow (Postdoctoral), National University of Singapore, Singapore (2009.10-2011.5)Research InterestsUsing synthetic inorganic chemistry and analytical chemistry as major tools to study the important enzymes (proteins) and other biomolecules. Currently, I have three projects in my lab.1. Direct electrochemistry of heme proteins.2. Enzyme mimetics based on metal or metal oxide nanostructures.3. Biosensors based on polydopamine or derivatives.Social ServiceThe member of Chinese Chemical Society.The Editorial Board Member of Scientific Reports (Chemistry).All Publications1.Mengmeng Guo, Muping Yu, Xiang Li, Maoguo Li*, “Immobilised cytochrome c onthe carbon dots functionalised MWCNTs and its application to hydrogen peroxide detection” International Journal of Environmental Analytical Chemistry 2017, 97, 1107–1118.2.Ding Hou, Haisheng Tao*, Xuezhen Zhu, Maoguo Li*, “Polydopamine and MnO2core-shell composites for high-performance supercapacitors” Applied Surface Science 2017, 419, 580–585.3.Yinling Wang*, Shengye Dong, Xiaoqin Wu, Xiaowang Liu, Maoguo Li*, “Core-shellN-doped carbon spheres for high-performance supercapacitors”,Journal of Materials Science2017, 52, 9673–7682.4.Yinling Wang,* Xiaoqin Wu, Xuemei Zhang, Maoguo Li*, “Chitosan, EDTA and cobaltsalts derived metal-N-C sub-micrometer spheres for high-performance oxygen reduction”, Journal of the Electrochemical Society 2017, 164, H389–H395.5.Xiujuan Wu, Miaomiao Yu, Xiaowang Liu, Maoguo Li*, “Low potentialdetermination of NADH at 1-Hydroxypyrene/reduced graphene oxide modified electrode”, International Journal of Electrochemical Science2017, 12, 4488–4501.6.Mengmeng Guo, Qikang Wu, Miaomiao Yu, Yinling Wang, Maoguo Li*, “One-stepliquid phase chemical method to prepare carbon-based amorphous molybdenum sulfides: As the effective hydrogen evolution reaction catalysts”, Electrochimica Acta 2017, 236, 280–287.7.Anna Li, Yuzhe Hu, Muping Yu, Xiaowang Liu, Maoguo Li*, “In situ growth of MoS2on carbon nanofibers with enhanced electrochemical catalytic activity for the hydrogen evolution”, International Journal of Hydrogen Energy2017, 42, 9419–9427.8.Jian Pang, Xiujuan Wu, Anna Li, Xiaowang Liu, Maoguo Li*,“Detection of catechinin Chinese green teas at N-doped carbon modified electrode”,Ionics2017,23, 1889–1895.9.Yinling Wang*, Shengye Dong, Xiaoqin Wu, Maoguo Li,“One-StepElectrodeposition of MnO2@NiAl Layered Double Hydroxide Nanostructures on the Nickel Foam for High-Performance Supercapacitors”, Journal of the Electrochemical Society 2017 164, H56–H62.10.Yinling Wang, Zhangcui Wang, Xiaoqin Wu, Xiaowang Liu, Maoguo Li*, "SynergisticEffect between Strongly Coupled CoAl Layered Double Hydroxides and Graphene for the Electrocatalytic Reduction of Oxygen", Electrochimica Acta2016, 192, 196–204.11.Yinling Wang*, Fajun Li, Shengye Dong, Xiaowang Liu, Maoguo Li*, “A facileApproach for Synthesizing Fe-Based Layered Double Hydroxides with High Purity and Its Exfoliation”, Journal of Colloid and Interface Science2016, 467, 28–34. 12.Yinling Wang*, Xuemei Zhang, Anna Li, Maoguo Li*,"Intumescent FlameRetardant-Derived P,N co-Doped Porous Carbon As an Efficient Electrocatalyst for the Oxygen Reduction Reaction", Chemical Communications2015,51, 14801–14804.13.Xuemei Zhang, Yinling Wang*, Shengye Dong, Maoguo Li*, "Dual-SitePolydopamine Spheres/CoFe Layered Double Hydroxides for Electrocatalytic Oxygen Reduction Reaction", Electrochimica Acta2015, 170, 248–255.14.Yinling Wang*, Zhangcui Wang, Yeping Rui, Maoguo Li*,“Horseradish PeroxidaseImmobilization on Carbon Nanodots/CoFe Layered Double Hydroxides: Direct Electrochemistry and Hydrogen Peroxide Sensing",Biosensors & Bioelectronics 2015,64, 57–62.15.Xiaoli Jiang, Yinling Wang*, Maoguo Li*,“Selecting Water-Alcohol Mixed Solventfor Synthesis of Polydopamine Nano-spheres Using Solubility Parameter”, Scientific Reports 2014, 4, Article Number 6070. DOI:10.1038/srep06070.16.Chang Guo, Lin Wang, Maoguo Li*,“Functionalization of Carbon Nanotubes withCopper for Nonenzymatic Electrochemical Detection of Glucose”, Nanoscience and Nanotechnology Letters 2014, 6(6), 481–487.17.Chang Guo, Maoguo Li*,“Synthesis and Cell Imaging of LaF3Nanocrystals withSmall Particle Size and Novel Upconversion Luminescence”, Acta Chimica Sinica 2014, 72(2): 215-219.18.Li Huang, Shoufeng Jiao, Maoguo Li*, “Determination of uric acid in human urineby eliminating ascorbic acid interference on copper(II)-polydopamine immobilized electrode surface”, Electrochim. Acta 2014, 121, 233–239.19.Yinling Wang*, Yeping Rui, Fajun Li, Maoguo Li,“Electrodeposition of NickelHexacyanoferrate/Layered Doublehydroxide Hybrid Film on the Gold Electrode and Its Application in the Electroanalysis of Ascorbic Acid”, Electrochim. Acta2014, 117, 398–404.20.Qian Song, Maoguo Li*, Li Huang, Qikang Wu, Yunyou Zhou*, Yinling Wang,“Bifunctional Polydopamine@Fe3O4 Core-Shell Nanoparticles for Electrochemical Determination of Lead (II) and Cadmium (II)”, Anal. Chim. Acta2013, 787, 64–70.21.Huiqing Ji, Maoguo Li*, Yinling Wang, Feng Gao, “Electrodeposition ofGraphene-Supported PdPt Nanoparticles with Enhanced Electrocatalytic Act ivity”, Electrochemistry Communications 2012,24, 17–20.22.Maoguo Li*, Huiqing Ji, Yinling Wang*, Lin Liu, Feng Gao, “MgFe-Layered DoubleHydroxide Modified Electrodes for Direct Electron Transfer of Heme Proteins”, Biosens. Bioelectron. 2012, 38, 239–244.23.Yinling Wang*, Huiqing Ji, Wei Peng, Lin Liu, Feng Gao, Maoguo Li*,“GoldNanoparticle-Coated Ni/Al Layered Double Hydroxides on Glassy Carbon Electrode for Enhanced Methanol Electro-Oxidation”, Int. J. Hydrogen Energy2012, 37, 9324–9329.24.Yinling Wang*, Wei Peng, Lin Liu, Feng Gao, Maoguo Li*, “The ElectrochemicalDetermination of L-Cysteine at a Ce-Doped Mg–Al Layered Double Hydroxide Modified Glassy Carbon Electrode”, Electrochim. Acta2012, 70, 193–198.25.Yinling Wang, Min Tang, Xinhua Lin, Feng Gao, Maoguo Li*, “Sensor for HydrogenPeroxide Using a Hemoglobin-Modified Glassy Carbon Electrode Prepared by Enhanced Loading of Silver Nanoparticle onto Carbon Nanospheres via Spontaneous Polymerization of Dopamine”, Microchim. Acta2012, 176, 405–410.26.Feng Gao*, Xinying Guo, Jun Yin, Dan Zhao, Maoguo Li and Lun Wang,“Electrocatalytic Activity of Carbon Spheres towards NADH Oxidation at Low Overpotential and Its Applications in Biosensors and Biofuel Cells”, RSC Adv.2011, 1, 1301–1309.27.Yinling Wang, Lin Liu, Maoguo Li*, Shudong Xu, Feng Gao*, “MultifunctionalCarbon Nanotubes for Direct Electrochemistry of Glucose Oxidase and GlucoseB ioassay”, Biosens. Bioelectron. 2011, 30, 107–111.28.Yan Wei, Qin-An Huang, Mao-Guo Li,Xing-Jiu Huang*, Bin Fang, Lun Wang*,“CeO2 Nanoparticles Decorated Multi-walled Carbon Nanotubes for Electrochemical Determination of Guanine and A denine”, Electrochim. Acta2011, 56, 8571–8575. 29.Feng Gao*, Peng Cui, Xiaoxiao Chen, Qingqing Ye, Maoguo Li, Lun Wang, “A DNAHybridization Detection Based on Fluorescence Resonance Energy Transfer between Dye-Doped Core-Shell Silica Nanoparticles and Gold N anoparticles”, Analyst2011, 136, 3973-398030.Yinling Wang*, Dandan Zhang, Wei Peng, Lin Liu, Maoguo Li*, “ElectrocatalyticOxidation of Methanol at Ni-Al Layered Double Hydroxide Film Modified Electrode in Alkaline M edium”, Electrochim. Acta2011, 56, 5754–5758.31.Yinling Wang*, Wei Peng, Lin Liu, Min Tang, Feng Gao, Maoguo Li*, “EnhancedElectrical Conductivity of Layered Double Hydroxide Modified Electrode by Graphene for Selectively Sensing of Dopamine”, Microchim. Acta2011, 174, 41–46. 32.Feng Gao*, Qingqing Ye, Peng Cui, Xiaoxiao Chen, Maoguo Li, Lun Wang,“Selective “turn-on” fluorescent sensing for biothiols based on fluorescence resonance energy transf er between acridine orange and gold nanoparticles”, Anal. Methods 2011, 3, 1180–1185.33.Lee Jin Tu Danence, Yaojun Gao, Maoguo Li,Yuan Huang, Jian Wang*,“Organocatalytic Enamide Azide Cycloaddition Reactions: Regiospecific Synthesis of 1,4,5-Trisubstituted-1,2,3-Triazoles”, Chem. Eur. J. 2011, 17, 3584–3587.34.Maoguo Li*,Shudong Xu, Min Tang, Lin Liu, Feng Gao, Yinling Wang*, “DirectElectrochemistry of Horseradish Peroxidase on Graphene-Modified Electrode for Electrocatalytic Reduction towards H2O2”, Electrochim. Acta2011,56, 1144–1149.35.Yaojun Gao, Qiao Ren, Hao Wu, Maoguo Li, Jian Wang*, “EnantioselectiveHeterocyclic Synthesis of Spiro Chromanone-Thiochroman Complexes Catalyzed by a Bifunctional Indane C atalyst”, Chem. Commun. 2010, 46, 9232–9234.36.Yinling Wang, Lin Liu, Dandan Zhang, Shudong Xu, Maoguo Li*, “A New Strategyfor Immobilization of Electroactive Species on the Surface of Solid Electrode”, Electrocatalysis2010, 1, 230–234.37.Fang Ni, Yinling Wang, Dandan Zhang, Feng Gao, Maoguo Li*,“Electroche micalOxidation of Epinephrine and Uric Acid at a Layered Double Hydroxide Film Modified Glassy Carbon Electrode and Its Application”, Electroanalysis2010,22, 1130–1135.38.Yinling Wang*, Dandan Zhang, Min Tang, Shudong, Xu, Maoguo Li*,“Electrocatalysis of Gold Nanoparticles/Layered Double Hydroxides Nanocomposites toward Methanol Electro-Oxidation in Alkaline Medium”, Electrochim. Acta2010, 55, 4045–4049.39.Feng Gao*, Jun Yin, Zhen Yao, Maoguo Li, Lun Wang, “A Nanocomposite ModifiedElectrode: Electrocatalytic Properties and Its Sensing Applications to Hydrogen Peroxide and Glucose”, J. Electrochem. Soc.2010, 157, F35–F39.40.Maoguo Li*, Fang Ni, Yinling Wang, Shudong Xu, Dandan Zhang, Lun Wang*,“LDH Modified Electrode for Sensitive and Facile Determination of Iodate”,Appl.Clay Sci. 2009, 46, 396–400.41.Yinling Wang, Shuihong Chen, Fang Ni, Feng Gao,Maoguo Li*, “Peroxidase-LikeLayered Double Hydroxide Nanoflakes for Electrocatalytic Reduction of H2O2”, Electroanalysis 2009, 21, 2125–2132.42.Maoguo Li*,Shudong Xu, Fang Ni, Yinling Wang, Shuihong Chen, Lun Wang*,“Fast and Sensitive Non-Enzymatic Glucose Concentration Determination Using Electroactive Anionic Clay Modified Electrode”, Microchim. Acta 2009,166, 203–208.43.Maoguo Li*, Fang Ni, Yinling Wang, Shudong Xu, Dandan Zhang, Shuihong Chen,Lun Wang*, “Sensitive and Facile Determination of Catechol and Hydroquinone Simultaneously under Coexistence of Resorcinol with a Zn/Al Layered DoubleHydroxide Film Modified Glassy Carbon Electrode”,Electroanalysis 2009, 21, 1521–1526.44.Maoguo Li*, Shuihong Chen, Fang Ni, Yinling Wang, Lun Wang*, “Layered DoubleHydroxides Functionalized with Anionic Surfactant: Direct Electrochemistry and Electrocatalysis of Hemoglobin”, Electrochim. Acta 2008, 53, 7255–7260.45.Bin Fang*, Shoufeng Jiao, Maoguo Li, Yuan Qu, Ximing Jiang, “Label-FreeElectrochemical Detection of DNA Using Ferrocene-Containing Cationic Polythiophene and PNA Probes on Nanogold Modified Electrodes”,Biosens.Bioelectron. 2008, 23, 1175–1179.46.Maoguo Li, Feng Gao, Ping Yang, Lun Wang*, Bin Fang, “Conveniently AssemblingDithiocarbamate and Gold Nanoparticles onto the Gold Electrode: A New Type of Electrochemical Sensors for Biomolecule Detection”,Surf. Sci. 2008, 602, 151–155.47.Yan Wei, Maoguo Li,Bin Fang*, “Fabrication of CeO2Nanoparticles ModifiedGlassy Carbon Electrode for Ultrasensitive Determination of Trace Amounts of Uric Acid in Urine”,Chin. J. Chem. 2007, 11, 1622–1626.48.Cai-yun Zheng, Shui-hong Chen, Yong-jia Shang*, Mao-guo Li*, “A Modified GlassyCarbon Electrode for Hydrogen Peroxide Sensing”,Annali Di Chimica2007,97, 1227–1235.49.Bin Fang*, Hongying Liu, Guangfeng Wang, Yunyou Zhou, Maoguo Li, Yan Yu, WeiZhang, “The Electrochemical Behavior and Direct Determination of Tyrosine at a Glassy Carbon Electrode Modified with Poly (9-Aminoacridine)”,Annali Di Chimica 2007, 97, 1005–1013.50.Bin Fang*, Yan Wei,Maoguo Li, Guangfeng Wang, Wei Zhang, “Study onElectrochemical Behavior of Tryptophan at a Glassy Carbon Electrode Modified with Multi-Walled Carbon Nanotubes Embedded Cerium Hexacyanoferrate”,Talanta 2007, 72, 1302–1306.51.Lun Wang*, Ping Yang, Yongxin Li, Hongqi Chen, Maoguo Li, Fabao Luo, “A FlowInjection Chemiluminescence Method for the Determination of Fluoroquinolone Derivative Using the Reaction of Luminol and Hydrogen Peroxide Catalyzed by Gold Nanoparticles”,Talanta 2007, 72, 1066–1072.52.Shoufeng Jiao, Maoguo Li, Cong Wang, Daolei Chen, Bin Fang*, “Fabrication ofFc-SWNTs Modified Glassy Carbon Electrode for Selective and Sensitive Determination of Dopamine in the Presence of AA and UA”,Electrochim. Acta 2007, 52, 5939–5944.53.Yan Wei, Guangfeng Wang, Maoguo Li, Cong Wang, and Bin Fang*, “Determinationof Rutin using a CeO2 Nanoparticle-Modified Electrode”, Microchim. Acta 2007, 158, 269–274.54.Yan Wei, Maoguo Li,Shoufeng Jiao, Qinan Huang, Guangfeng Wang, Bin Fang*,“Fabrication of CeO2Nanoparticles Modified Glassy Carbon Electrode and Its Application for Electrochemical Determination of UA and AA Simultaneously”, Electrochim. Acta 2006, 52, 766–772.55.Bin Fang*, Shoufeng Jiao, Maoguo Li, Haisheng Tao, “Simultaneous Determinationof Uric Acid and Ascorbic Acid at a Ferrocenium–Thioglycollate Modified Electrode”, Anal. Bioanal. Chem. 2006, 386, 2117–2122.56.Yongjia Shang*, Chenli Fan, Maoguo Li,Caiyun Zheng, “Synthesis and PropertiesStudy of Novel Ferrocenyl Isoxazole Derivatives”,Appl. Organometal. Chem. 2006, 20, 626–631.57.Bin Fang*, Wenzhi Zhang, Xianwen Kan, Haisheng Tao, Xianhui Deng, Maoguo Li,“Fabrication and Application of a Novel Modified Electrode Bas ed on β-Cyclodextrin/ Ferrocenecarboxylic Acid Inclusion Complex”,Sensor. Actuat. B2006,117, 230~235.58.Bin Fang*, Xiang-hui Deng, Xian-wen Kan, Hai-sheng Tao, Wen-zhi Zhang, MaoguoLi, “Electrochemical and Electrocatalytic Properties of Ferrocene Incorporated in L-Cysteine Self-Assembled Monolayers on a Gold Electrode”, Anal. Lett. 2006, 39, 697–707.59.Maoguo Li,Yong-Jia Shang, Ying-Chun Gao, Guang-Feng Wang, Bin Fang*,“Preparation of Novel Mercury-Doped Silver Nanoparticles Film Glassy Carbon Electrode and Its Application for Electrochemical Biosensor”, Anal. Biochem. 2005, 341, 52–57.60.Maoguo Li,Ying-Chun Gao, Xian-Wen Kan, Guang-Feng Wang, Bin Fang*, “Effectof Ag Nanoparticles for Electrochemical Sensing of Brilliant Cresyl Blue”,Chem. Lett.2005, 34, 386–387.61.Maoguo Li,Yin-Ling Wang, Guang-Feng Wang, Bin Fang*, “ElectrochemicalDetermination of 6-Mercaptopurine at Silver Microdisk Electrodes”,Annali Di Chimica 2005, 95, 685–693.62.Bin Fang*, Guangfeng Wang, Wenzhi Zhang, Maoguo Li,Xianwen Kan,“Fabrication of Fe3O4Nanoparticles Modified Electrode and Its Application for Voltammertric Sensing of Dopamine”,Electroanalysis 2005, 17, 744–748.63.Bin Fang*, Guangfeng Wang, Maoguo Li, Yingchun Gao, Xianwen Kan, Prepartionof Ag Nanoparticles/L-Cysteine Modified Gold Electrode and Its Application.Chimica Analyticzna 2005, 50, 419–423.64.Xianwen Kan, Xianghui Deng, Wenzhi Zhang, Guangfeng Wang,Maoguo Li,Haisheng Tao, Bin Fang*, “Electrocatalytical Oxidation of Hydroquinone with Ferrocene Covalently Bound to L-Cysteine Self-Assembled Monolayers on a Gold Electrode”,Annali Di Chimica 2005, 95, 593–600.65.Bin Fang, Yingchun Gao, Maoguo Li, Yongxin Li*, “Application of Functionalized AgNanoparticles for the Determination of Proteins at Nanogram Levels Using Resonance Light Scattering Method”,Microchim. Acta 2004, 147, 83–86.66.Guangfeng Wang, Maoguo Li, Yingchun Gao, Bin Fang*, “An Amperometric SensorUsed for Determination of Thiocyanate with Silver Nanoparticles Modified Electrode”, Sensors 2004, 4, 147–155.67.Yongxin Li, Changqin Zhu, Lun Wang*, Feng Gao, Maoguo Li,Leyu Wang,“Application of Manganese-Tetrasulfonatophthalocyanine as a New Mimetic Peroxidase in the Determination of Hydrogen Peroxide Based on the Chemiluminescence Reaction of Luminol with Hydrogen Peroxide”,Anal. Lett. 2001, 34, 1841–1850.68.阚显文, 张文芝, 邓湘辉, 陶海升, 李茂国, 方宾*, 抗坏血酸在β-环糊精/二茂铁甲酸修饰电极上的电化学行为及测定, 分析化学, 33 (2005) 1573-1576.69.杨小红, 王广凤, 邓湘辉, 张文芝, 李茂国, 阚显文, 方宾*, 纳米Fe3O4修饰电极的制备及其催化应用, 应用化学, 22 (2005) 776-779.70.王广凤, 李茂国, 阚显文, 高迎春, 方宾*, 纳米银粒子复合修饰电极的制备及对苯二酚的测定, 应用化学, 22(2005) 167-171.71.李茂国, 王广凤, 高迎春, 方宾*, 纳米银修饰电极对痕量硫氰根的测定, 理化检验,41(2005) 305-307.72.李茂国, 王广凤, 周运友, 方宾*, 银催化甲醛前行动力波的研究, 分析化学, 32 (2004)1223-1226.73.陶海升, 李茂国, 吴丽芳, 方宾*, 电化学氟化最新进展, 化学进展, 16 (2004) :213-219.74.高迎春, 李茂国, 王广凤, 方宾*, 银纳米修饰电极的制备及其对灿烂甲酚蓝的催化研究,分析试验室, 23 (2004) 78-81.75.阚显文, 李茂国, 陶海升, 张德兴, 杜俊, 方宾*, 电位滴定法同时测定电合成产物苯甲醛和苯甲酸, 应用化学, 20 (2003) 699-701.76.杜俊, 李茂国, 高迎春, 阚显文, 方宾*, Cu(II)-α-氨基酸配合物的紫外光谱性质及组成测定, 光谱实验室, 20 (2003) 415-418.77.汪乐余, 郭畅, 李茂国, 许发功, 朱昌青, 王伦*, 功能性硫化镉纳米荧光探针荧光猝灭法测定核酸, 分析化学, 31 (2003) 83-86.78.李茂国, 许发功, 方宾*, 银微盘电极上谷胱甘肽降解产物的伏安行为, 分析测试学报,22 (2002) 56-58.79.商永嘉*, 李茂国, 陆婉芳, 王彦广, 新型含酰胺键的噻二唑类液晶的合成, 高等学校化学学报, 23 (2002) 576-580.80.朱英贵, 张明翠, 李茂国, 王伦*, 含偶氮基的Schiff碱-高锰酸钾-硫酸化学发光体系研究,安徽师大学报, 25 (2002) 161-163.81.李茂国, 张龙, 方宾*, 微分电位溶出法测柠檬酸, 安徽师大学报, 23 (2000) 256-258.82.周运友, 方宾*, 李茂国, 1-4-巯甲基苯的合成及其电化学性质研究, 化学试剂, 21 (2000)121-122.83.张玉忠, 李蜀萍, 阚显文, 李茂国,方宾*, 头孢拉定降解产物在银亚微电极上的电化学行为, 分析化学, 28 (2000) 127.84.张玉忠, 李蜀萍, 阚显文, 李茂国, 方宾*, 头孢噻肟钠降解产物在银微电极上阴极溶出示差脉冲伏安法测定, 分析化学, 28 (2000) 1371-1374.85.李茂国, 方宾*, 间接碘量法误差问题讨论, 安徽师大学报, 21 (1998) 279-281.86.周运友, 郭荷民, 方宾*, 朱英贵, 李茂国, 陶海升, 对苄二硫醇在玻碳汞膜电极上吸附伏安行为的研究, 安徽师大学报, 21 (1998) 152-155.。

NiFe双氢纳米粒子有效提高BiVO4光阳极光电化学水分解性能

© 2018, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.
In recent years, solar‐driven photoelectrochemical (PEC) water splitting, which is an efficient, environmentally friendly, and sustainable technique, has attracted considerable attention [1,2]. Improvements in the sunlight‐absorption properties, conversion efficiencies, and catalytic activities of photoelec‐ trode materials are crucial in the use of PEC for transforming solar energy into chemical energy [3,4]. Various photoelectrode materials such as TiO2 [5,6], WO3 [7,8], and α‐Fe2O3 [9,10] have been widely studied and used for efficient production of hy‐ drogen at the photocathodes of PEC cells. The use of BiVO4 in PEC water splitting is increasing because of its small bandgap (Eg = 2.4–2.5 eV), which enables significant visible‐light absorp‐

二维层状双金属氢氧化物在去除磷酸盐中的应用

化工进展Chemical Industry and Engineering Progress2022年第41卷第7期二维层状双金属氢氧化物在去除磷酸盐中的应用杨靖1，范议议1，王赛娣1，王福凯1，孟秀霞1，杨乃涛1，刘少敏2（1山东理工大学化学化工学院，山东淄博255049；2北京化工大学化学工程学院，北京100029）摘要：层状双金属氢氧化物（LDH ）是磷酸盐去除的良好吸附剂，具有表面易改性、电荷可调、层间距可控、吸附能力强和吸附速度快的特点，能够有效解决水体富营养化问题。

本文从LDH 除磷性能的优化出发，综述了LDH 的结构特征、除磷机理、制备方法、剥离方法的前沿理论和应用案例；基于目前LDH 用作磷酸盐吸附剂面临着易团聚、胶体溶液不稳定、性能受控于pH 以及难回收等问题，分析了磁性LDH 、生物炭/LDH 、GO(rGO)/LDH 等复合材料的复合方法和性能改进方案，指出了LDH 复合改性和LDH 膜材料的研究新趋势，以及主要研究重点与热点。

希望本文能够为LDH 在水处理领域的研究提供新思路，为深入优化LDH 吸附和膜分离性能提供理论支持和方向引导。

关键词：层状双金属氢氧化物；功能性LDH 复合材料；阴离子；去除磷酸盐；吸附中图分类号：X703.1文献标志码：A文章编号：1000-6613（2022）07-3689-18Layered double hydroxide (LDH)for phosphate removalYANG Jing 1，FAN Yiyi 1，WANG Saidi 1，WANG Fukai 1，MENG Xiuxia 1，YANG Naitao 1，LIU Shaomin 2(1School of Chemistry and Chemical Engineering,Shandong University of Technology,Zibo 255049,Shandong,China;2School of Chemical Engineering,Beijing University of Chemical Technology,Beijing 100029,China)Abstract:Layered double hydroxide (LDH)is an excellent adsorbent for the removal of phosphate anions,which is featured by easy modification,adjustable surface charge,layer spacing controlling,strong adsorption capacity and fast adsorption rate,showing effectiveness to address the issues of eutrophication of water bodies.Proceeding from optimization of phosphate removal properties,this review summarizes the LDH structural features,adsorption mechanism,the frontier theories of the delamination and some application cases.Some challenges are pointed out including the easy aggregation,unstable colloidal solution,performance controlled by pH,as well as the difficulty to recycle LDH as the anion adsorbent.To solve these problems,some composite method and improving scheme for magnetic LDH,biochar/GO,GO (rGO)/LDH copositive materials are analyzed.LDH composite modification and LDH membrane materials are proposed as the new research trend and hot study.It is hopeful that this review can provide some new ideas for new researchers to begin their work in this area using LDH for applications in water treatment.Theoretically,it is general guidelines for the adsorption of phosphate anions on LDH and membrane separation performance.综述与专论DOI ：10.16085/j.issn.1000-6613.2021-1694收稿日期：2021-08-09；修改稿日期：2021-10-21。

硅学报,2009,缓释型萘系减水剂的合成

· 1103 ·第36卷第7期缓释型萘系减水剂的合成王素娟1，严云1,2，胡志华1,2(1. 西南科技大学材料科学与工程学院；2. 先进建筑材料四川省重点实验室，四川绵阳 621010)摘要：用尿素法制备了镁铝层状双金属氢氧化物(MgAl–layered double hydroxide–like host materials，MgAl–LDHs)，采用焙烧复原法将商品萘系减水剂插入MgAl–LDHs的层间，得到了一种缓释型萘系高效减水剂。

采用热重–同步差热分析、X射线衍射和红外光谱分别对MgAl–LDHs、焙烧后的镁铝层状双金属氧化物(magnesium aluminum layered double oxide，MgAl–LDO)和用萘系减水剂插层MgAl–LDHs的产物等的结构进行了表征，分析了不同焙烧温度对插层组装效果的影响，并测试了掺此种减水剂的水泥净浆流动度的经时变化。

结果表明：在500℃焙烧得到的MgAl–LDO，其层状结构可以恢复。

萘系减水剂插层后，MgAl–LDHs的X射线衍射特征峰向小角度移动，层间距由原来的0.76nm增大到1.03nm；红外光谱在1035.6cm–1和1123.1cm–1处出现了萘系减水剂中SO3–基团的吸收峰，且MgAl–LDHs中NO3–基团的吸收峰明显减弱。

与基准相比，此减水剂具有明显的减小水泥净浆流动度经时损失的效果。

关键词：层状双金属氢氧化物；萘系减水剂；插层；水泥净浆；流动度中图分类号：TU528 文献标志码：A 文章编号：0454–5648(2009)07–1103–07SYNTHESIS OF CONTROLLED RELEASE NAPHTHALENE-BASED SUPERPLASTICIZERW ANG Sujuan1，YAN Yun1,2，HU Zhihua1,2(1. Department of Material Science and Engineering, Southwest University of Science and Technology; 2. Key Laboratory forAdvanced Building Materials of Sichuan Province, Mianyang 621010, Sichuan, China)Abstract: A novel controlled-release naphthalene-based superplasticizer with features of lower flowability loss of cement pastes was synthesized by intercalating naphthalene-based superplasticizer molecules into the galleries of layered double hydroxide–like host materials (MgAl–LDHs) by calcine-recovering method, which was prepared by co-precipitation techniques (urea method). The re-sulting materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and thermogravim-etry–synchronization differential thermal analysis. The effect of calcining temperature on the intercalation efficiency of naphtha-lene-based superplasticizer molecules was investigated, and then the flowability of cement paste blended with superplasticizer varying with time was analyzed. The results indicate that the magnesium aluminum layered double oxide (MgAl–LDO) which was obtained by calcining MgAl–LDHs at 500 can be recovered. The primary℃XRD peak of MgAl–LDHs intercalated by naphthalene-based superplasticizer molecule shifts towards a low angle value and the interlayer spaces expand from 0.76 to 1.03nm, which can be at-tributed to the insertion of organic naphthalene-based superplasticizer molecules into the interlayer space of the host materials. The FTIR spectroscopy of controlled release naphthalene-based superplasticizer shows the new absorption peaks at 1035.6 and 1123.1 cm–1, in which indicates the presence of SO3– within the galleries of the host materials, and the absorption peak of nitrate anions weakened obviously. Compared to the control mix, the controlled release naphthalene-based superplasticizer molecules have a promi-nent effect on reducing the loss of flowability of cement pastes.Key words: layered double hydroxides; naphthalene-based superplasticizer; intercalation; cement paste; flowability随着混凝土的生产和应用技术迅速发展，混凝土的用量急剧增加，使用范围日益扩大。

超薄双金属氢氧化物纳米片的干法剥离用作氧析出反应电催化剂

超薄双金属氢氧化物纳米片的干法剥离用作氧析出反应电催化剂庄林【期刊名称】《物理化学学报》【年(卷),期】2017(033)008【总页数】2页(P1499-1500)【作者】庄林【作者单位】武汉大学化学与分子科学学院,武汉430072【正文语种】中文体相层状双金属氢氧化物(layered double hydroxides，简称LDHs)由于其独特的二维结构、大的比表面积以及其特殊的电子结构显示出良好的电催化性能，其用于氧析出反应(oxygen evolution reaction，简称OER)已有了广泛的研究1。

但是，大的颗粒尺寸和颗粒的厚度限制了电催化活性位点的暴露从而抑制了其OER的电催化活性。

研究表明，相比体相LDHs，单层的二维超薄LDHs纳米片具有更高的比表面，易于暴露更多的电催化活性位点，有利于提高OER的电催化活性2。

目前，二维超薄的LDHs纳米片的合成，主要通过液相剥离法剥离，例如表面活性剂分子插层辅助剥离法、表面活性剂剥离法等3。

然而，液相剥离法由于其工艺复杂、耗时长、成本高并且表面溶液吸附溶剂分子，从而限制了其大规模生产。

另外，在二维超薄的LDHs纳米片的基面内引入缺陷是提高OER电催化活性的另外一种方法4。

因而，寻找一种工艺简单，耗时短，成本低的LDHs剥离方法，同时又能够在二维基面引入缺陷的方法，仍然是一大挑战。

目前为止，此类方法尚未见报到。

最近湖南大学王双印教授课题组，利用等离子体技术干法剥离体相钴铁双金属氢氧化物纳米片(CoFe LDHs)，得到富含缺陷的二维超薄纳米片，相关结果发表在Angewandte Chemie International Edition杂志上5。

该课题组首次利用Ar等离子体一步干法剥离体相层状双金属氢氧化物形成二维超薄纳米片，同时在二维超薄纳米片基面内引入缺陷。

此种剥离的方法耗时短、成本低、避免了液相剥离时溶剂分子的吸附而且易于大规模生产。

氮掺杂科琴黑碳材料的制备及电催化氧还原性能研究

氮掺杂科琴黑碳材料的制备及电催化氧还原性能研究刘冠良; 刘鹏; 余林; 孙明; 程高【期刊名称】《《无机盐工业》》【年(卷),期】2019(051)010【总页数】5页(P84-88)【关键词】科琴黑; 氮掺杂碳材料; 吡啶氮; 氧还原【作者】刘冠良; 刘鹏; 余林; 孙明; 程高【作者单位】广东工业大学轻工化工学院广东广州510006【正文语种】中文【中图分类】TQ127.1可持续的清洁能源是人类社会发展的基础，其中，燃料电池和金属空气电池作为一种新型清洁能源电池，因其较高的理论容量和环境友好的特点，受到科研工作者的广泛研究和关注［1-3］。

然而，燃料电池和金属空气电池正极上的氧还原反应（ORR）因其复杂的四电子过程和缓慢的动力学过程，成为限制这两种设备商业化应用的重要原因［4-5］。

铂碳是目前性能较为优异的氧还原催化剂，但是因为金属铂价格高昂、容易中毒失活和稳定性较差，严重限制了铂碳催化剂的大规模应用，因此开发非贵金属氧还原催化剂具有十分重要的意义［6］。

碳材料具有环境友好，价格低廉的优点，其中科琴黑因其具有较大的比表面积和优异的导电性能，常被用于各种电池中。

但到目前为止，较少文章将科琴黑用作电催化氧还原催化剂。

为了进一步提高碳材料的电催化活性，有必要对碳材料表面进行掺杂和改性［7］。

对碳材料掺杂后，掺杂原子和碳原子的电负性会被相互改变，从而促进材料表面原子对氧气的吸附能力和还原能力。

在众多掺杂原子中，氮原子掺杂碳材料由于活性及稳定性较高，而且掺杂的材料对环境友好，是目前研究的最广泛的掺杂方式［8-10］。

科琴黑的大比表面积使其在与氮源混合过程中能够更加充分的接触。

本文使用廉价易得的氮源（尿素和三聚氰胺），采用固相焙烧法，在高温和惰性气氛的作用下，在科琴黑碳材料表面掺入不同类型的氮原子以提高其电催化氧还原性能。

XPS表征表明，以三聚氰胺为氮源比以尿素为氮源能够在科琴黑碳材料表面产生更多吡啶氮。

石墨烯制备方法总结-高勇讲解

石墨烯（Graphene）的制备方法总结石墨烯（Graphene）是一种由碳原子以sp2杂化轨道组成六角型呈蜂巢状晶格的平面薄膜，是一种只有一个原子层厚（0.334nm）的二维材料。

石墨烯分为：1单层石墨烯（Graphene）；2 双层石墨烯（Bilayer or double-layer graphene）；3 少层石墨烯（few-layer）3-10层；4 多层或者厚层石墨烯（multi-layer graphene）厚度在10层以上10nm以下。

石墨烯（Graphenes）是一种二维碳材料，是单层石墨烯、双层石墨烯、多层石墨烯的总称。

制备不同种类的石墨烯有不同的方法，一般情况下，制备单层石墨烯的方法有：机械剥离法、化学气象沉积法、外延生长法、有机合成法等；制备多层石墨烯的方法有：氧化还原法、电弧放电法等；制备石墨烯纳米带的方法：熔融合金快淬碳自析法等。

目前为止，国内外的石墨烯制备方法有20多种，其中包括：1.机械剥离法2.氧化还原法3.外延生长法4.有机合成法5.化学气象沉积法（CVD）6.化学剥离法（氧化还原法）7.球磨法8.熔融合金快淬碳自析法9.电化学法10.石墨插层法11.离子注入法12.高温高压生长法（HTHP）13.爆炸法14.液相气象直接剥离法15.等离子体增强化学气象沉积法（PECVD）16.原位自生模板法17.电泳沉积法18.微波法19.溶剂热法20.电弧放电法21.固态碳源催化法22.纳米管切割法每一种制备方法的原理、制备的石墨烯质量、工艺过程及评价：（1）化学气象沉积法（CVD）原理：CVD法是可控制备大面积石墨烯的一种最常用的方法。

它的主要原理是利用平面金属作为基底和催化剂，在高温环境中通入一定量的碳源前驱体和氢气，相互作用后在金属表面沉积而得到石墨烯。

从生长机理上主要可以分为两种:一是，渗碳析碳机制，即对于镍等具有较高溶碳量的金属基体，碳源裂解产生的碳原子在高温时渗入金属基体内，在降温时再从其内部析出成核，进而生长成石墨烯；二是，表面生长机制，即对于铜等具有较低溶碳量的金属基体，高温下气态碳源裂解生成的碳原子吸附于金属表面，进而成核生长成“石墨烯岛”，并通“石墨烯岛”的二维长大合并得到连续的石墨烯薄膜。

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