Opto-electronic Properties of Graphene Oxide and Partially Oxidized Graphene

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石墨烯变形

• 先在乙醇中分别超声分散，再混合搅拌。
• 核壳结构的PS-GO微球是通过 PS与GO间的π-π共轭作用。
J. Mater. Chem, 2011, 21, 6916–6921
Directing Silicon−Graphene Self-Assembly as a Core/Shell Anode for High-Performance Lithium-Ion Batteries
文献五：Graphene Oxide Nanosheet Wrapped White-Emissive Conjugated Polymer Nanoparticles
(a) Schematic illustration of the preparation of GO-PFO NPs. SEM image of GO-PFONPs.
J. Mater. Chem. C,2014, 2, 6462–6466
文献四：Graphene oxide coated core–shell structured polystyrene microsph eres and their electrorheological characteristics under applied electric ﬁeld
石墨烯/聚合物变形
郑冉冉秦雪藏冰刘成 20140915
一、快速蒸干溶剂法
文献一：Hierarchical Nanohybrids with Porous CNT-Networks Decorated Crumpled Graphene Balls for Supercapacitors
石墨烯褶皱微球：
二、通过GO的自组装，在聚合物微球上包覆GO法。
文献二：Graphene-Wrapped Hybrid Spheres of Electrical Conductivity

石墨烯

1 Department 2 Department ∗
of Physics, Shanghai Normal University, Shanghai 200234, China of Electrical Engineering, Yale University, New Haven, Connecticut 06520, USA 3 ﬂiu@
© 2015 Optical Society of America
OCIS codes: (230.4555) Coupled resonators; (050.6624) Subwavelength structures; (130.3120) Integrated optics devices; (300.1030) Absorption; (300.3700) Linewidth.
11. H. Lu, C. Zeng, Q. Zhang, X. Liu, M. M. Hossain, P. Reineck, and M. Gu, “Graphene-based active slow surface plasmon polaritons,” Sci. Rep. 5, 8443 (2015). 12. H. Lu, “Plasmonic characteristics in nanoscale graphene resonator-coupled waveguides,” Appl. Phys. B. 118, 61–67 (2015). 13. F. Bonaccorso, Z. Sun, T. Hasan, and A. C. Ferrari, “Graphene photonics and optoelectronics,” Nat. Photonics 4, 611–622 (2010). 14. F. Xi

High performance supercapacitors based on reduced graphene oxidenext term in aqueous and ionic liqui

High performance supercapacitors based on reduced graphene oxide in aqueous and ionic liquid electrolytesYao Chena ,b,Xiong Zhang a ,Dacheng Zhanga ,b,Peng Yua ,b,Yanwei Maa ,*a Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,PR China bGraduate University of Chinese Academy Sciences,Beijing 100049,PR ChinaA R T I C L E I N F O Article history:Received 28May 2010Accepted 29September 2010A B S T R A C TPartially reduced graphene oxide (RGO)has been fabricated using hydrobromic acid.Since hydrobromic acid is a weak reductant,some oxygen functional groups which are relatively stable for electrochemical systems remain in RGO.Therefore,RGO can be re-dispersed in water and 2–3layers of graphene can be observed by transmission electron microscopy,showing excellent afﬁnity with water.RGO facilitates the penetration of aqueous electro-lyte and introduces pseudocapacitive effects.Moreover,its capacitive nature is enhanced after cycling measurements.It is concluded that the increase of capacitance is due to the reduction of the oxygen functional groups by the cyclic voltammetry and electrochem-ical impedance spectroscopy analysis.The electrochemical properties in the ionic liquid electrolyte,1-butyl-3-methylimidazolium hexaﬂuorophosphate (BMIPF 6),are also investi-gated.At a current density of 0.2A g À1,the maximum capacitance values of 348and 158F g À1are obtained in 1M H 2SO 4and BMIPF 6,respectively.Ó2010Elsevier Ltd.All rights reserved.1.IntroductionSupercapacitors have attracted much interest as one of the energy storage systems.They can be used either by them-selves as the primary power source or in combination with batteries or fuel cells.They exhibit such high power density that they can complement the deﬁciency of rechargeable bat-teries in the energy storage ﬁeld.There are two energy storage mechanisms for supercapacitors:double-layer capacitance and pseudocapacitance.Although the energy densities of de-vices based on pseudocapacitance are greater than those on double-layer capacitance,the phase changes in the pseudoc-apacitance materials limit their lifetime and power density due to the faradic reaction.So far,various carbon materials,metal oxides and conducting polymers have been used as supercapacitor electrode materials.As we know,carbon materials,commonly corresponding to double-layer capaci-tance,are the most ideal materials for supercapacitors.Theincrease in capacitance of carbon materials is achieved mainly by optimization of porosity and surface treatments to promote wettability [1–3].Graphene,which was discovered by Geim’s group in 2004,is a single layer of carbon atoms densely packed into a ben-zene-ring structure [4].Nowadays,chemically modiﬁed graphene obtained by simple chemical processing of graphite [5,6]has become the most promising carbon material on the application of supercapacitors due to its peculiar properties such as high speciﬁc surface area and good electrical conduc-tivity [7,8].More importantly,unlike activated carbon,the high effective speciﬁc surface of graphene does not depend on the distribution of pores [9]but layers.Since Vivekchand et al.[10]and Stoller et al.[7]pioneered supercapacitors based on graphene by thermal and chemical methods,respectively,graphene-based supercapacitors have developed to be widely attractive in the study of the energy storage devices [11–14].Currently,monolayers of graphene using chemical methods0008-6223/$-see front matter Ó2010Elsevier Ltd.All rights reserved.doi:10.1016/j.carbon.2010.09.060*Corresponding author:Fax:+861082547137.E-mail address:ywma@ (Y.Ma).were commonly fabricated by adding toxic hydrazine with ammonia to graphite oxide(GO)colloids[15].However,when they are re-dispersed in water,aggregation can be observed due to its hydrophobic surface property.It can induce harsh aqueous electrolyte penetration[16].To enhance the electro-chemical properties of graphene,our group had attemptted to introduce pseudocapacitance by absorbing N atoms on graphene[17,18].In fact,remaining some desirable O atoms on graphene can introduce wettability and pseudocapaci-tance more conveniently and effectively.In addition,most GO-based electrode materials,such as GO/polyaniline[19], are fabricated in acid environment by one-step method.They are prepared more easily than those corresponding graphene composites,but their electrochemical properties may be opti-mized when removing extra O element in GO.On the basis of the two aspects,an acid weak reductive needs to be discov-ered to reduce GO.To develop high performance supercapacitors,the narrow electrochemical window is needed to overcome.Apart from fabricating asymmetric devices[20],employing other non-aqueous electrolytes can break through the limited potential of1V in aqueous system.Conventional organic electrolytes, like tetraethylammonium tetraﬂuoroborate and triethylme-thylammonium tetraﬂuoroborate in acetonitrile,have been applied on supercapacitors with a relatively large potential window.However,electrolyte depletion upon charge,narrow operational temperature range and low safety problem are three main drawbacks for organic electrolytes.Ionic liquids have been used to replace the organic electrolytes in a wide range of applications.Their larruping properties including large liquid phase range,wider electrochemical window and high safety make them excellent electrolytes for various elec-trochemical systems.Unfortunately,carbon nanotubes with-out complicated plasma etching[21]exhibit very limited capacitance(below25F gÀ1)in ionic liquid electrolytes[22,23].In this work,we have prepared the reduced graphene oxide(RGO)by impregnating hydrobromic acid,an acid weak reductant,into homogeneous GO colloids.Subsequently,the electrochemical properties of RGO in both aqueous and ionic liquid electrolytes are investigated.Some oxygen functional groups remains in RGO,leading to additional pseudocapaci-tance for the RGO electrodes.As a result,at the current den-sity of0.2A gÀ1we have obtained the maximum speciﬁc capacitance of348and158F gÀ1in1M H2SO4and1-butyl-3-methylimidazolium hexaﬂuorophosphate(BMIPF6),respec-tively.So far,this wonderful capacitance of348F gÀ1is the highest value for all electrode materials of chemically modi-ﬁed graphene.More surprisingly,the capacitance of RGO in-creases continuously as cycle numbers increase,which are associated with the residual oxygen functional groups of RGO.2.Experimental2.1.Preparation of samplesGO was synthesized by the modiﬁed Hummers’methods [17,24].0.1g of GO in100mL of water was sonicated and then loaded in a round-bottomﬂask.Next,hydrobromic acid(3mL, 40wt.%)was added into the GO colloids.The mixtures were reﬂuxed in an oil bath at110°C for24h.Finally RGO was ob-tained afterﬁltration,washing with water and desiccation.A control experiment without HBr was carried out in order to conﬁrm that the reduction is not a result of elevated temper-ature alone.2.2.Characterization of samplesX-ray photoelectron spectroscope(XPS)spectra were recorded on a PHI Quantear SXM(ULVAC-PH INC)which used Al as an-ode probe in 6.7·10À8Pa.The thermogravimetric analyse (TGA)of GO and RGO was done in Dupont1090B.The weight loss of the samples was monitored from room temperature to 950°C at a heating rate of10°C minÀ1in nitrogen atmo-sphere.X-ray diffraction(XRD)patterns were performed using a X’Pert Pro system with Cu K a radiation.Raman spec-tra were obtained on a RM2000microscopic confocal Raman spectrometer(Renishaw in via Plus,England)employing a 514nm laser beam.UV–vis spectra were detected using Ultra-violet spectrophotometer(Hitachi UV2800).Solid-state13C nuclear magnetic resonance(NMR)spectra was collected by AVANCE III400(NanoBay)on the condition that the sample was spun at10kHz to average the anisotropic chemical shift tensor.Atomic force microscopy(AFM)image was taken out using a Nanoscope III MultiMode SPM(Digital Instruments) operated in tapping mode.Transmission electron microscopy (TEM)morphology was investigated by JEOL JSM2010.The electrical conductivity of bulk RGO by pressing the powder at10MPa in room temperature was detected with a physical property measurement system(Quantum Design,PPMS).2.3.Electrochemical measurementsAll electrochemical experiments were carried out using a three-electrode system.The working electrode materials composed of RGO,acetylene black and polyvinylidene diﬂuo-ride with a weight ratio of7:2:1were pasted on the titanium substrates to form very homogeneousﬁlms with a surface density of0.2mg cmÀ2.The accurate weight of the electrodes was read by a high-precision balance(AB135-S,Mettler Tole-do,d=0.00,001g).A slice of platinum was used as the auxil-iary electrode and a saturated calomel electrode(SCE)for 1M H2SO4aqueous system or a piece of silver wire for the pure ionic liquid BMIPF6electrolyte as the reference electrode. Specially,the beaker-type electrochemical cells in the ionic liquid system were sealed in an Ar glove box.All cyclic voltammetry(CV),galvanostatic charge/discharge and elec-trochemical impedance spectroscopy(EIS)were performed with CHI660C workstation.The EIS plots were tested in the frequency range from100kHz to0.1Hz at open circuit poten-tial with an ac perturbation of5mV.3.Results and discussionAs well known,GO is composed of hydroxyl and aether groups on both sides and carboxyl ones on the edge.Although hydrobromic acid is not as efﬁcient as hydrazine hydrate to reduce the monolayer of GO(Fig.S1),it can also have ring-opening reaction with aether groups[25].Thus impregnating574C A R B O N49(2011)573–58026%of O in the control bining with a much low-er amount of C–O and C@O bonds for RGO in comparison with the control sample in their C1s spectra(Fig.S2c),it suggests that HBr is indispensable in reducing GO to get a higher C/O ratio.But20%of oxygen remained in RGO is still higher than 11%in graphene using hydrazine hydrate as reducing reagent [15,26].Furthermore,only0.26%of Br in RGO is presented in Fig.S2b,meaning that bromine element is hardly introduced. Fig.2shows the C1s XPS of GO and RGO.The intensities of C–O(286.6eV)and the C@O(287.6eV)in RGO are much smaller than those of GO.In addition,the C@O peak in RGO shifting to289.0eV may be due to the dehydration between carboxyl and hydrobromic acid.The XRD pattern of RGO exhibits one broad peak at about18°for(002)and the other peak for(010)(see Fig.S3),illuminating that the(002)spac-ing of GO reduces from0.72to0.49nm.However,it is still lar-characterizations,so we use NMR to further analyze RGO.In the spectra of RGO(Fig.3),the maximum peak at125ppm rep-resents sp2carbons of the graphene network.In contrast to GO reported previously[5],the peak intensity at71ppm arisen from hydroxyl groups is very small in comparison with the maximum peak of RGO.Moreover,the peak of epoxide groups at about60ppm for GO is not evident in the spectra of RGO. These results indicate that epoxide groups can be reduced more easily than hydroxyl ones.The Raman spectra of GO and RGO are shown in Fig.4.After reduction,the D/G intensity ratio of GO increases from0.78to0.89,inferring that more defects form when some oxygen atoms are removed.This con-sists with the explanation that new created graphitic domains are smaller in size and more numerous in number[5].Although the as-made RGO colloids whose TEM imageFig.1–The TGA of GO and RGO.Fig.3–NMR spectrum of RGO.densities of0.2,0.5and1A gÀ1.We calculate the speciﬁc capacitance in this method based on Eq.(2):C¼iD tm D Vð2Þwhere i is discharged current and D t is discharged time in the potential window D V.The highest speciﬁc capacitance of 348F gÀ1at0.2A gÀ1,higher than any other capacitance val-ues in a three-electrode system,is obviously assigned to the residual oxygen in graphene planes producing extra pseudoc-apacitive effects and excellent afﬁnity with water[31].The hydrophilic nature facilitates the penetration of aqueous elec-trolyte.However,according to the report[32],an effective spe-ciﬁc capacitance should be evaluated in a two-electrode system.So a symmetrical coin cell in the aqueous electrolyte has been fabricated and its capacitance values reach111and 129F gÀ1at50and10mV sÀ1,which is slightly lower than a three-electrode system(see Fig.S6and Table S1).The cycling durability of RGO in aqueous electrolyte is pre-sented by CV at10mV sÀ1in Fig.6d.To be surprised,the capacitance of RGO does not degrade but increase continu-ously until the2000th cycle.Concretely,it breaks through 125%of the initial capacitance after1800cycles and is stillabove120%after3000cycles.In order to study the mecha-nism of the peculiar phenomenon,we analyze the change of the CV and EIS plots through repetitive measurements. From Fig.6e,the current of redox peaks in CVs increases with cycling.After cycling,the anode peak at0.334V vs.SCE shifts to0.456V and the cathode peak from0.262to0.272V.The signiﬁcant rise in cathode peak current mainly contributes to the additional capacitance.Considering that the behaviour is similar to the electrochemical reduction of GO[33],the abnormal increased capacitive effects must be attributed to the reduction of oxygen groups.As expected,GO with too much oxygen has not a comparable capacitance,proven by Fig.S7.So the amount of residual oxygen in RGO is stable and desirable in the electrochemical system because the ini-tial value is close to the maximum one in the life data.The amazing results are beneﬁcial to the application of graph-ene-based supercapacitors.The EIS spectrums also depict the difference after various cycle numbers in Fig.6f.The equivalent circuit[34,35]and theﬁtting results of the RGO electrode are exhibited in Fig.S8and Table S2.At the high fre-quencies,the intercept at real part equaling to the internal resistance(Rs)decreases slightly from0.91to0.87X after 3000cycles due to removing some oxygen by the electro-chemical reduction,reﬂecting that20%of oxygen does not re-sult in an sharp increase of Rs.The semicircle in the high-frequency range associated with the surface properties of the porous electrode corresponds to the faradic charge-trans-fer resistance(R1)[36,37].Fewer hopping sites offered by oxy-gen on the surface of RGO in slow kinetics faradaic reactions to enhance the mobility of proton renders that R1increases from1.5to7X after2000cycles[34,38].A slight decrease of R1at the3000th cycle to5.3X may be caused by improving distributed electrolyte resistance[2]after long-term penetra-phase element(CPE2),where its parameter CPE2-P represents an ideal capacitor described with a vertical line in low-fre-quency region if it equals to1[1].Based on the fact that the parameter is changed from0.75at the1800th to0.8at the 2000th cycle,it is concluded that the ideal double-layer capac-itance dominates capacitive nature at the moment.In order to extend the potential window of the RGO sup-ercapacitors,BMIPF6,a kind of ionic liquid,is used to be the electrolyte.The electrochemical window of2.4V in a three-electrode system is wide enough.Fig.7panels a and b show the CV and galvanostatic charge/discharge curves of RGO, respectively.We get the highest capacitance of130and 158F gÀ1at the condition of1mV sÀ1and0.2A gÀ1,respec-tively,much better than that of carbon nanotubes in this sys-tem[22].In contrast to the aqueous system,the internal resistance of54X is much higher(Fig.S9)as the conductivity of the ionic liquid with a high viscosity is lower than1M H2SO4solution.4.ConclusionsWe have employed a novel reductant of HBr to synthesize RGO as the electrode of supercapacitors.More importantly, HBr may be applied to reduction of GO-based electrode mate-rials in an acid environment.Although some oxygen func-tional groups in GO are removed,RGO still shows the afﬁnity with water which promotes the wettablity of the elec-trode materials.At the current density of0.2A gÀ1,the maxi-mum speciﬁc capacitance values reach348and158F gÀ1in the aqueous and BMIPF6electrolytes,respectively.The resid-ual oxygen on the surface of RGO greatly affects the capaci-tance and life time performance.On one hand,under the premise of not deteriorating the internal resistance,these rel-578C A R B O N49(2011)573–580AcknowledgementsThis work was partially supported by the Knowledge Innova-tion Program of the Chinese Academy of Sciences(No.KJCX2-YW-W26),the National Natural Science Foundation of China (No.21001103)and the Director Foundation of Institute of Electrical Engineering.Appendix A.Supplementary dataSupplementary data associated with this article can be found, in the online version,at doi:10.1016/j.carbon.2010.09.060.R E F E R E N C E S[1]Kotz R,Carlen M.Principles and applications ofelectrochemical capacitors.Electrochim Acta2000;45(15–16):2483–98.[2]Pandolfo AG,Hollenkamp AF.Carbon properties and theirrole in supercapacitors.J Power Sources2006;157(1):11–27. 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基于石墨烯超材料的宽频带可调太赫兹吸波体

第19卷第6期太赫兹科学与电子信息学报Vo1.19，No.62021年12月 Journal of Terahertz Science and Electronic Information Technology Dec.，2021文章编号：2095-4980(2021)06-0973-06基于石墨烯超材料的宽频带可调太赫兹吸波体胡丹1，付麦霞2，朱巧芬3(1.安阳师范学院物理与电气工程学院，河南安阳 455000；2.河南工业大学信息科学与工程学院，河南郑州 450001；3.河北工程大学数理科学与工程学院，河北邯郸 056038)摘要：基于二维材料石墨烯，设计了一款宽频带可调谐超材料太赫兹吸波体。

该吸波体由三层结构组成，顶层为石墨烯超材料，中间层为二氧化硅，底层为金属薄膜。

仿真结果表明，当石墨烯的费米能级为0.7eV时，该吸波体在1.11~2.61THz频率范围内吸收率超过90%，相对吸收带宽为80.6%。

当石墨烯的费米能级从0eV增大到0.7eV时，该吸波体器件的峰值吸收率可以从20.32%增大到98.56%。

此外，该吸波体器件还具有极化不敏感和广角吸收的特性。

因此，它在太赫兹波段的热成像、热探测、隐身技术等领域具有潜在的应用价值。

关键词：超材料；太赫兹；吸波体；石墨烯中图分类号：TN29文献标志码：A doi：10.11805/TKYDA2021248Tunable broadband terahertz absorber based on graphene metamaterialHU Dan1，FU Maixia2，ZHU Qiaofen3(1.School of Physics and Electrical Engineering，Anyang Normal University，Anyang Henan 455000，China；. All Rights Reserved.2.College of Information Science and Engineering，Henan University of Technology，Zhengzhou Henan 450001，China)3.School of Mathematics and Physics Science and Engineering，Hebei University of Engineering，Handan Hebei 056038，China)Abstract：A tunable broadband terahertz absorber based on graphene metamaterial is proposed and numerically demonstrated. The absorber consists of three layers: the upper is the graphene metamateriallayer, the middle is the SiO2layer, and the bottom is the metallic layer. Simulation results demonstratethat the proposed absorber achieves over 90% absorption in 1.11- 2.61THz with a relative bandwidth of80.6%when Fermi level c=0.7eV. The peak absorption rate of the proposed absorber can be tuned from20.32%to 98.56%by changing the Fermi energy of graphene from 0eV to 0.7eV. Additionally, theproposed absorber is insensitive to polarization and has high absorbance to wide incidence angles. Suchdesign may have some potential applications in thermal imaging, thermal detecting, and stealth technique.Keywords：metamaterial；terahertz；absorber；graphene超材料吸波体具有厚度薄、质量轻、吸收能力强、高度集成等优点，并且可以“量需定制”。

“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。

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。

可调谐石墨烯光电子器件

可调谐石墨烯光电子器件作者：何晓勇刘春林赵振宇张浩石旺舟来源：《上海师范大学学报·自然科学版》2015年第04期Abstract： Due to the excellent optical，mechanical and thermal properties，graphene is one of the most important topics in many research fields.Since the linear dispersion relationship near the Dirac point can be tuned conveniently by using the applied gate voltage，magnetic fields，and temperature，graphene layer is a good platform to investigate the tunable devices.We give a brief presentation of graphene tunable devices in the terahertz，nearInfrared and midInfrared spectral regions.It benefits to the investigation of the tunable optoelectronics devices in the future.Key words： graphene； terahertz； tunable devices1 IntroductionGraphene，a flat monolayer of carbon atoms packed into a dense twodimensional （2D）honeycomb crystal lattice，has unique thermal，mechanical，and electrical properties，such as the anomalous quantum Hall effect，Shubnikovde Haas oscillations and Klein paradox to coherent transport[1-2].It can also interact strongly with light in a broad frequency regime with the help of doping or regular structured patterns，e.g. the monolayer graphene can be observed under an optical microscope with the naked eyes[3].The conductivity of graphene can also be modified by means of chemical doping，electric field，or magnetic field.Graphene surface plasmons （SPs）（GSPs）display favorable properties of low losses，extreme confinement，and high tenability[4-5].Furthermore，besides the usual transverse magnetic plasmons，when the imaginary part of graphene conductivity is negative，it support a transverse electric mode[6].Graphene TE modes reside very close to the light line and display great potential for future optoelectronic devices.With those excited electronic transport properties，graphene can serve as a good platform for further exploration of plasmonic devices[7-8].Recently，graphene have been widely adopted to fabricate tunable optoelectrical devices.For instance，through the coupling between spatially separated graphene sheets，splitter and ultracompact modulator have been pared with the presented devices，the graphene modulators have several distinctive advantages[9-11]：（1） Strong lightgraphene interaction.A monolayer graphene possesses a much stronger interband optical transition than the quantum well systems；（2） Broadband operation.The graphene devices covers all telecommunications bandwidth and also the midand farinfrared；（3） Highspeed operation.Because the carrier mobility of the graphene layer is very high （ideally can reach 2×105 cm2·V-1·s-1），the Fermi level can be rapidly modulated.Furthermore，due to the short photocarrier generation and relaxation time，the graphene modulators operate on the timescale of ps，and the modulation speed can reach more than 500 GHz，depending on the carrier density and graphene quality.Consequently，graphene has been identified as a potential tunable plasmonic material in wide spectral ranges，which provides a wealth of opportunity for technological exploitation in free space communication，security，biosensing，and trace gas detection.To give a good understanding of the tunable devices nowadays，we give a brief introduction of the graphene based tunable devices in the fields of THz，nearInfared and midIR regimes.The permittivity of monolayer graphene in the THz regime can be found in Figure 2.Because the energy of the THz wave is small，the intraband contribution dominates.As shown in Eq.（3），the conductivity and permittvity of the graphene layer is closely related to the Fermi level.3 Graphene supported tunable devices3.1 Tunable THz graphene devicesDue to the small energy of THz waves，the intraband contribution dominates，leading to the carrier concentration and conductivity of the graphene layer increase significantly，as shown in Fig.2.By depositing graphene microribbon on the SiO2/Si substrate，Ju，et.al. investigated the tunable properties of the graphene plasmon resonances in the THz regime，as shown in Fig.3[13].The results show that the graphene SPs resonances can be modulated in a broad THz regime by changing the iongel top gating and ribbon width at room temperature.The width of graphene ribbon is in the range of several micrometers.When the polarization of the incident light is perpendicular to the ribbon，the graphene microstructure displays large oscillator strengths，leading to the prominent roomtemperature absorption peaks.Even for monolayer graphene，the microstructure shows more than 10% absorption，which represents the strong lightplasmon coupling in graphenesupported THz metamaterials.In 2013，by depositing metallic electronic splitring resonators on the monolayer graphene，the hybrid graphene/metamaterials structure has been suggested to achieve the modulation of THz waves.The results show that by applying the gate voltage，the modulation depth of THz waves at low frequency resonance （LC resonance） can reach 11.5%，the corresponding applied bias is 10.6V[14].By using topgated architecture and measuring the back reflection curves，Degl′Innocenti，et.al. realized the active modulation of THz waves between 2.2 and 3.1 THz.The maximum modulation depth can reach more than 18%，and the low bias is as low as 0.5 V[15].In 2015，based on the mechanisms of extraordinary optical transmission （EOT） effect，the transmission shows an enhancement of several orders of magnitude with respect to the classical aperture theory，Gao，et.al. proposed the metallic ring apertures/graphene layer structure to achieve the large amplitude modulation of THz waves[16].The amplitude modulation of THz waves reach more than 50%，and the EOT phenomenon induce seven times nearfield enhancement of THz absorption of graphene layer.By depositing monolayer graphene on the Al SRR subwavelength MMs，the group in Tianjin University proposed the grapheneSi hybrid structures to realize the active modulation of incident THz waves in a wide range，as shown in Fig.5.The thickness of the Al MMs unit cell structure is 200 nm.The low frequency resonant dip locates about 0.67 THz.With the help of optical pump light （532 nm，280 mW），the generated carriers of the photodoped Si layer diffuse into the graphene layer，improving an efficient tuning of the Fermi level.Consequently，a small applied voltage will significantly change the graphene conductivity and modulate the terahertz waves.The hybrid MMs structure manifests a large modulation depth of amplitude of 60% at extremely low bias voltages （lower than 5V）.The modulation speed is about several KHz[17].By using the multiarrays of large area graphene supercapacitors，a new kind of broadband THz spatical light passive modulator has been proposed.It can be found from Fig.5 that an ionic electrolyte is sandwiched between two large area graphene layer （5 cm×5 cm） to generate charge densities on the order of 1014 cm-2，corresponds to Fermi energies of 1 eV.By changing the applied voltage bias，the transmittance of THz waves passing through the modulators with high modulation depth and low operation voltage is achieved.When the gate voltage changes from 0-2V，the transmittance can be tuned 30%-65%[18].As shown in Fig.6，by depositing the graphene metamaterial （MM） patterns on the flexible polymer substrates，He，et.al. proposed the SiO2/Si （GSiO2Si） structures to realize large modulation of THz waves[19].This investigation shows that the tuning mechanism of the GSiO2Si structure mainly depends on dipolar resonance，different from the conventional metallic MM structure based on the LC resonance.The modulation depth of transmission is about 80%.As the Fermi level of the graphene layer increases，the resonant transmission become stronger，and the resonant dips significantly shift to higher frequency.Additionally，by depositing the graphene patterns on the flexible substrate，the complementary grapheneSiO2Si （cGSiO2Si） structures have also been proposed to realize dynamic control of the propagation waves.As shown in Fig.7[20]，the transmission and reflection resonant curves of the complementary graphene MMs based on the eSRRs unit cell have been suggested.The results manifest that the tunable mechanisms of the complementary graphene MMs structures mainly depend on the LC resonance.The resonant transmission and reflection properties of the complementary graphene MMs structures can be tuned over a wide range via controlling the applied electric fields.As the Fermi level of the graphene layer increases，the resonances of the MMs structure become stronger，and the resonant peaks of the transmission curves shift to the higher frequency.The transmission reflection curve is sharp，which can be used to fabricate transmission reflection filters.3.2 Tunable nearIR devicesRecently，by stacking multilayers of grapheneSi3N4 in the slot of Si waveguides，a novel nearIR polarizer has been demonstrated[21].When the layer number of the graphene（0.34 nm）Si3N4（56 nm） unit cell is larger than 6，the polarizer shows good performance.Based on the mechanisms that the loss of the graphene TE modes is much smaller than that of the TM modes，for the 7 micrometer long devices，a good TE mode polarizer can be obtained.For instance，the insertion losses of the TM modes is about 31.5 dB，and the TE modes losses is very small，only about 0.2 dB.Because the graphene layer can interact with the incident light significantly，Lu and Zhao suggested thenanoscale graphene electrooptical modulator in the nearinfrared regime[22].Fig.8（a） shows the graphene based Si waveguides，i.e.the monolayer graphene is inserted between the doped Si layer.Fig.8（b） is the attenuation of above structure versus wavelength at different Fermi levels[22]The fermi lelve of the graphene layer can be modulated by the applied gate voltage.The influence of the Fermi level on the attenuation of the above structure can be found in Fig.9（b）.The length of the graphene modulator is about 800 nm.Because the graphene permittivity changes obviously with the alternatation of the Fermi level，the attenuation of the EO modulator can be modulated in a wide range，leading to the propagation modes changes significantly，which are confirmed by the 3D FDTD results.In the nearIR spectral region，the energy of the incident light is large，when the Fermi level is low，the graphene behaviors like dielectric layer； when the Fermi level increase aboutμc=0.5×hω，the interband dominates，the dielectric constant of the graphene layer versus Fermi level shows a dip.Based on this tunable mechanism，He，et.al. show that a metamaterial in combination with graphene，i.e. by integrating the metallic metamaterials （MMs） with a graphene layer，has better modulation properties than existing materials in the nearinfrared region，and is tunable[23-24].Owing to the tunability of the Fermi level of graphene，the resonance of transmitted or reflected curves can be tuned in a wide range （160-193 THz）.To an original metal unit cell structure，an elevated Fermi level of graphene layer enhances the resonance dips and shifts it to the higher frequency.Furthermore，the corresponding complementary MMs structure shows a much sharper spectral curve and can be used to fabricate a switcher or filters.3.3 Tunable THz MidIR devicesBesides in the THz and nearIR regimes，graphene based plasmonic device in the midIR regime have also been recently explored.As shown in Fig.10，Xia′s group experimentally studied the damping mechanisms of graphene SPs （GSPs），indicating that the surface polar phonons in the SiO2 substrate leading to the significant plasmon dispersion and damping.The results manifest that theoptimal wavelength for the GSPs device locate in the subterahertz regime，which is very helpful in designing novel graphene plasmonic waveguide devices.By depositing metallic arrays on the monolayer graphene，the midIR plasmonic modulators have been proposed.By changing the conductivity of the graphene layer，the reflection amplitude and phase can be tuned in a wide range.The thickness of the SiO2 layer is 285 nm.The intensity modulation with onoff extinction ratio can exceed 100，and the phase modulation is over 240 degree.The modulation rate can is on the order of several GHz.By changing the bias voltage，the resonant wavelength was shifted by 0.85 μm，about 8.5% of the central frequency[26].By depositing the metallic MMs unit cell on the uniform monolayer graphene，which is on the top of a dielectric spacer layer and metallic substrate，the graphenebased tunable MidIR absorber has been demonstrated.Because the carrier concentration and conductivity of the graphene changes significantly with the increase of Fermi level，the graphene layer near the MMs resonator.The SRRs unit cell MMs structure shows larger spectral shift.The resonant absorption peak displays a large shift，about 30%.The possible reason is that the SRRs unit cell structure can produce the largest electric fields among them，which perturbs the MMs absorber propertiessignificantly.Simultaneously，the value of the absorption keeps relatively larger，above 0.9 in the midIR regime，which means that the graphene tunable absorber structure can be used to fabricate efficient absorber and switchers[27].In the MidInfrared region，the graphene represents a very thin plasmonic material and can be used to fabricate tunable devices.Mousavi，et.al. demonstrated that by integrating the Fano resonant plasmonic metasurfaces[28]，the single layer graphene can be used to tune the midinfrared optical response in a wide range.Furtheremore，the spectral sharp changes little.Due to the strong inductive coupling between the metasurfaces and graphene layer，the proposed structure manifests obviously blue shift tunability when the Fermi level of the graphene layer increases.The experimental results displayed that the blue shift of the resonances can reach about 30 cm-1[28].4 ConclusionIn summary，to reach a good understanding of the tunable optoelectronics deives nowadays，we present a brief introduction of the graphene based tunable devices in the fields of THz，nearInfared and midIR regimes.The tunable mechanisms at different specral regions have also been shown.The results show that in the THz regime，because the incident light energy is small，the intraband contribution is dominant，leading to the carrier concentration and permittivity of the graphene layer changes significantly.While in the nearIR regime，the incident light energy is relative larger，the interband contribution dominants，the graphene behaves like a thin dielectriclayer.Especially，when the Fermi level of the graphene layer reach about half of the incident light energy，the graphene permittivity shows dip.The results benefits the investigation of the mechanisms and fabribation of the graphene based tunable devices in the future.References：[1]GEIM A K.Graphene：status and prospects[J].Science，2012，324（5934）：1530-1534.[2]NOVOSELOV K S，GEIM A K，MOROZOV S V，et al.Twodimensional gas of massless Dirac fermions in graphene[J].Nature，2005，438（7065）：197-200.[3]LIU M，YIN X，ERICK U A，et al.A graphenebased broadband opticalmodulator[J].Nature，2011，474（7349）：64-67.[4]ZHAN D，YAN J，LAI L，et al.Engineering the electronic structure of graphene[J].Adv Mater，2012，24（30）：4055-4069.[5]LEE S H，CHOI M，KIM T T，et al.Switching terahertz waves with gatecontrolled active graphene metamaterials[J].Nat Mater，2012，11（3）：936-941.[6]BAO Q，ZHANG H，WANG B，et al.Broadband graphene polarizer[J].Nat Photonics，2011，5（7）：411-415.[7]WANG F，ZHANG Y，TIAN C，et al.Gatevariable optical transitions ingraphene[J].Science，2008，320（5873）：206-209.[8]BONACCORSO F，SUN Z，HASAN T，et al.Graphene photonics and optoelectronics[J].Nat Photonics，2010，4（9）：611-612.[9]GEIM A K，NOVOSELOV K S.The rise of graphene[J].Nat Mater，2007，6（3）：183-191.[10]GARCIA DE ABAJO F J.Graphene plasmonics：challenges and opportunities[J].ACS Photonics，2014，1（3）：135-152.[11]AVOURIS P.Graphene：electronic and photonic properties and devices[J].Nano Lett，2010，10（11）：4285-4294.[12]HANSON G W.Quasitransverse electromagnetic modes supported by a graphene parallelplate waveguide[J].J Appl Phys，2008，104（8）：084314.[13]JU L，GENG B，HORNG J，et al.Graphene plasmonics for tunable terahertz metamaterials[J].Nat Technol，2011，6（10）：630-634.[14]VALMORRA F，SCALARI G，MAISSEN C，et al.Lowbias active control of terahertz waves by coupling largearea CVD graphene to a terahertz metamaterial[J].Nano Lett，2013，13（7）：3193-3198.[15]DEGL′INNOCENTI R，JESSOP D S，SHAH Y D，et al.Lowbias terahertz amplitude modulator based on splitring resonators and graphene[J].ACS Nano，2014，8（3）：2548-2554.[16]GAO W，SHU J，REICHEL K，et al.Highcontrast terahertz wave modulation by gated graphene enhanced by extraordinary transmission through ring apertures[J].Nano Lett，2014，14（3）：1242-1248.[17]LI Q，TIAN Z，ZHANG X，XU N，et al.Dual control of active graphenesilicon hybrid metamaterial devices[J].Carbon，2015，90：146-153.[18]KAKENOV N，TAKAN T，OZKAN V A，et al.Grapheneenabled electrically controlled terahertz spatial light modulators[J].Opt Lett，2015，40（9）：1984-1987.[19]HE X Y.Tunable terahertz graphene metamaterials[J].Carbon，2015，82：229-237.[20]HE X Y，LIU C L，ZHONG X，et al.Investigation of the tunable properties of graphene complementary terahertz metamaterials[J].RSC Adv，2015，5（16）：11818-11824.[21]YIN X，ZHANG T，CHEN L，et al.Ultracompact TEpass polarizer with graphene multilayer embedded in a silicon slot waveguide[J].Opt Lett，2015，40（8）：1733-1736.[22]LU Z，ZHAO W.Nanoscale electrooptic modulators based on grapheneslot waveguides[J].J Opt Sco Am B，2012，29（6）：1490-1496.[23]HE X Y，ZHAO Z Y，SHI W Z.Graphenesupported tunable nearIR metamaterials[J].Opt Lett，2015，40（2）：178-181.[24]BALASUBRAMANIAN N.Nano focus graphene meets metamaterial[J].MRS Bulletin，2015，40（4）：304-304.[25]YAN H，LOW T，ZHU W，et al.Damping pathways of midinfrared plasmons in graphene nanostructures[J].Nat Photonics，2013，7（5）：394-399.[26]LI Z，YU N.Modulation of midinfrared light using graphenemetal plasmonicantennas[J].Appl Phys Lett，2015，102（13）：131108.[27]VASIC B，GAJIC R.Graphene induced spectral tuning of metamaterial absorbers at midinfrared frequencies[J].Appl Phys Lett，2013，103（16）：261111.[28]MOUSAVI S H，KHOLMANOV I，ALICI K B，et al.Inductive tuning of Fanoresonant metasurfaces using plasmonic response of graphene in the midinfrared[J].Nano Lett，2013，13（3）：1242-1248.摘要：凭借着良好的光电、力学和热学性能，石墨烯是目前凝聚态物理领域一个重要的研究热点.而且由于石墨烯的色散关系在狄拉克点附近呈现线性特性，石墨烯的光电特性可以通过外加电场、磁场和温度来加以调节.因此，石墨烯是研究可调谐器件的良好平台.基于石墨烯的电导率随费米能级有明显改变的特点，在分析石墨烯器件的调制机制的基础上，对石墨烯可调谐器件在太赫兹、中红外和近红外的应用发展进行了综述研究.关键词：石墨烯；太赫兹；可调谐器件（责任编辑：顾浩然，包震宇）。

The electronic properties of graphene

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©2009 The American Physical Society
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Graphene was eventually spotted due to the subtle op-
tical effect it creates on top of a chosen SiO2 substrate ͑Novoselov et al., 2004͒ that allows its observation with
For Evaluation Only.
eﬁt of hindsight, no experimental tools existed to search
for one-atom-thick ﬂakes among the pencil debris cov-
ering macroscopic areas ͑Geim and MacDonald, 2007͒.
REVIEWS OF MODERN PHYSICS, VOLUME 81, JANUARY–MARCH 2009
The electronic properties of graphene
A. H. Castro Neto Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA

详细-介绍石墨烯英文版解析

Graphene is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice The name ‘graphene’ comes from graphite + -ene = graphene
Third, industrial use of graphene as a transparent conductor could have huge implications for the solar industry. As synthetic routes improve, the prospect of replacing ITO with a low-cost carbon-based coating seems feasible. This would not only remove significant uncertainty about the availability and cost of indium but also enable non evaporative roll-to roll processing of transparent conductors.
In 2004: Andre Geim and Kostya Novoselov at Manchester University managed to extract single-atom-thick crystallites (graphene) from bulk graphite: Pulled out graphene layers from graphite and transferred them onto thin silicon dioxide on a silicon wafer in a process sometimes called micromechanical cleavage or, simply, the Scotch tape technique. Since 2004, an explosion in the investigation of graphene in term of synthesis, characterization, properties as well as specifical potential application were reported.

Graphene-based electrodes for electrochemical energy storage

1
Introduction
Graphene is a single layer of sp2 carbon atoms arranged hexagonally. Graphene has a high intrinsic carrier mobility (200 000 cm2 VÀ1 sÀ1),1 excellent thermal conductivity ($5000 W mÀ1 KÀ1),2–4 high optical transmittance ($97.7%),5 high theoretical specic surface area (2630 m2 gÀ1),6 and superior mechanical strength.1 Thus, graphene is envisioned to nd a wide spectrum of applications.7–16 As graphite consists of single graphene layers connected via van der Waals forces, it is not unexpected that graphene can be produced by exfoliation of graphite physically17 or chemically.18,19 The chemical exfoliation approach, however, generally yields a chemically modied graphene, which has a signicantly lower electric conductivity than pristine graphene.20 In the chemical exfoliation method, highly oxidative chemicals are used to loosen the van der Waals forces

Understanding the Properties of Graphene Oxide

Understanding the Properties ofGraphene OxideGraphene oxide (GO) is a material that has garnered a lot of attention in the scientific community due to its unique properties and potential applications. In this article, we will explore the properties of graphene oxide and why it is such a promising material.1. What is Graphene Oxide?Graphene oxide (GO) is a derivative of graphene, a two-dimensional material made up of a single layer of carbon atoms arranged in a honeycomb structure. GO is produced by the oxidation of graphene, which involves adding oxygen-containing groups to the surface of the material.The resulting material has a layered structure that is similar to graphite, but with oxygen-containing functional groups attached to the surface of each layer. These functional groups make GO hydrophilic, meaning it is soluble in water and other polar solvents, unlike pure graphene which is hydrophobic.2. Properties of Graphene OxideGraphene oxide possesses a number of unique properties that make it an appealing material for researchers. Some of its notable properties include:2.1. Electrical PropertiesGraphene oxide is an electrically insulating material due to the presence of oxygen-containing functional groups on its surface, which disrupt the flow of electrons. However, these functional groups can be removed through a process called reduction, which results in a material with electrical conductivity comparable to graphene.2.2. Mechanical PropertiesGraphene oxide is a mechanically robust material that can withstand high tensile stress despite being only a few atoms thick. It is also highly flexible, making it an ideal candidate for use in flexible electronics.2.3. Optical PropertiesGraphene oxide exhibits unique optical properties that are different from those of pure graphene. It has a strong absorption band in the ultraviolet region of the spectrum, making it useful for applications such as UV filters. It also has a comparatively low reflectivity in the visible region of the spectrum.2.4. Chemical PropertiesGraphene oxide is a highly reactive material due to the presence of oxygen-containing functional groups on its surface. These functional groups can undergo chemical reactions with other molecules or materials, allowing for the integration of graphene oxide into a variety of different applications.3. Applications of Graphene OxideDue to its unique properties, graphene oxide has the potential to be used in a wide range of applications. Some notable applications of graphene oxide include:3.1. Energy StorageGraphene oxide has been shown to be an effective material for energy storage due to its high specific surface area, which allows for the efficient storage of energy. It has been used in the development of supercapacitors, batteries, and fuel cells.3.2. SensorsGraphene oxide is highly sensitive to changes in its environment, making it an ideal material for use in sensors. It has been used in the development of biosensors, gas sensors, and pH sensors.3.3. Water PurificationGraphene oxide has been shown to be an effective material for water purification due to its high surface area and hydrophilic nature. It has been used in the development of water filters that can remove contaminants such as heavy metals and bacteria from water.4. ConclusionIn conclusion, graphene oxide is a highly promising material that has attracted a lot of attention in the scientific community due to its unique properties and potential applications. Further research is needed to fully understand the properties of graphene oxide and its potential applications, but it is clear that this material has the potential to revolutionize a wide range of industries.。

Graphene-based optical modulator 超全面的石墨烯介绍

Novoselov et al, Science 306, 666 (2004) insets in (C).
Klein paradox – electrons go through
potential s
Penetration of particles through potential barriers. The transmission probability T is directionallydependent. For high barriers (V >> E)
a consequence of the unusual lowenergy electronic structure of monolayer graphene that features electron and hole conical bands meeting each other at the Dirac point
Fractional Quantum Hall effect
Quantum Hall effect times rational fractions. Not completely understood.
/812/effe.htm
Anomalous quantum Hall effect
Among strongest bonds in nature
A. K. Geim & K. S. Novoselov. The rise of graphene. Nature Materials Vol 6 183-191 (March 2007)
5 mm
The Nobel Prize in Physics for 2010 Andre Geim Kostya Novoselov

Graphene A Wonder Material 石墨烯：一种神奇材料

Graphene: A Wonder Material 石墨烯：一种神奇材料作者：来源：《时代英语·高三》2022年第02期導读：石墨烯，一种神奇的材料，能够让有语言障碍的人“说话”，从此不再被交流困扰。

如今，中国正大力发展石墨烯在各个领域内的应用……How wonderful it would be if new technology could help the physically challenged. A smart wearable device that enables people with speaking disabilities to communicate normally is giving hope to those without a voice.Tao Luqi， a research fellow at Chongqing University， used a material called graphene to produce an artificial throat with a tiny sensor that allows people with speech impairments to speak normally， according to a paper published in Nature Communications. Tao has continued his work on the device for the last few years.Although it’s a tiny mechanical sensor， it can work wonders. The device can detect weak vibrations and can produce sounds across a wide spectrum， from 100 Hz to 40 kHz， China Daily reported. Humans can detect sounds in a frequency range from 20 Hz to 20 kHz.如果新技术能帮助残障人士该有多好。

石墨烯的功能化

© XXXX American Chemical Society
A B B C D G H I K M N N Q R R S S S S S T T T
A
1. INTRODUCTION Graphene, the two-dimensional sp2-hybridized carbon, is currently, without any doubt, the most intensively studied material. This single-atom-thick sheet of carbon atoms arrayed in a honeycomb pattern is the world’s thinnest, strongest, and stiﬀest material, as well as being an excellent conductor of both heat and electricity. It is no wonder that this two-dimensional material is considered, from the application viewpoint, to be even more promising than other nanostructured carbon allotropes, that is, 1-dimensional nanotubes and 0-dimensional fullerenes. Since the ﬁrst experimental evidence of the electronic properties of graphene in 2004,1 a major focus of experimental research has been concentrated on the development of new synthetic routes enabling an eﬀective production of well-deﬁned sheets.2−18 The commonly applied methods include the micromechanical1 or chemical exfoliation of graphite,13 chemical

泡沫基材-Ni-石墨烯复合镀层制备及电催化析氢性能研究

第53卷第2期表面技术2024年1月SURFACE TECHNOLOGY·221·泡沫基材-Ni-石墨烯复合镀层制备及电催化析氢性能研究秦海森1,2*，刘丽2，张凤2，孙大明1，彭云1（1.成都工业学院电子工程学院，成都 611700；2.西南石油大学新能源与材料学院，成都 610500）摘要：目的采用电沉积技术在泡沫基材上沉积制备Ni-石墨烯复合镀层，期望借助泡沫基材的三维多孔结构和石墨烯的超高比表面积来改变复合材料的表面状态，进而获得高镀层的电催化析氢性能。

方法采用电沉积技术将石墨烯作为第二相粒子沉积，制备了泡沫基材-Ni-石墨烯复合电极，通过SEM和EDS研究了其微观形貌及成分，并利用电化学工作站完成了镀层电极的极化曲线、交流阻抗和电解水稳定性测试，使用控制变量法探究了镀层厚度、镀液石墨烯浓度和基材形貌对镀层电催化析氢活性的影响。

结果 SEM和EDS 表征发现，镀层表面形貌受镀液中石墨烯浓度影响较大，石墨烯作为第二相嵌入镀层后，明显改变了复合镀层的表面形貌，其存在形态为颗粒状，在150 mg·L–1时颗粒堆积最多。

进一步利用电化学分析技术探究了镀层厚度、镀液石墨烯浓度和基材形貌对电极电催化析氢性能的影响，发现在一定范围内，不同厚度镀层的电催化析氢活性基本相同；石墨烯质量浓度为150 mg·L–1时制得的电极的电催化析氢性能最优，析氢过电位为211.2 mV（vs. RHE），且电解水稳定性良好；泡沫基材镀层的电催化析氢活性明显优于平板基材镀层。

结论石墨烯的引入和泡沫基材三维多孔结构均增大了复合镀层的比表面积，是电极表现良好的电催化析氢活性的关键。

关键词：电沉积；石墨烯；泡沫基材；Ni基复合镀层；析氢活性中图分类号：TG174.4 文献标志码：A 文章编号：1001-3660(2024)02-0221-09DOI：10.16490/ki.issn.1001-3660.2024.02.022Preparation and Electro-catalytic Hydrogen Evolution Performance of Foam Substrate-Ni-Graphene Composite CoatingQIN Haisen1,2*, LIU Li2, ZHANG Feng2, SUN Daming1, PENG Yun1(1. School of Electronic Engineering, Chengdu Technological University, Chengdu 611700, China;2. School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China)ABSTRACT: In this paper, the foam substrate-Ni-graphene composite electrode was prepared by depositing graphene as the second phase particle on the foam substrate. The concentration gradient of graphene was 0 mg·L–1, 50 mg·L–1, 10 mg·L–1, 150 mg·L–1, 200 mg·L–1, and 250 mg·L–1. It was expected to change the surface state of the composite material with the three-dimensional porous structure of the foam substrate and the ultra-high specific surface area of the graphene, so as to obtain收稿日期：2022-11-29；修订日期：2023-03-21Received：2022-11-29；Revised：2023-03-21基金项目：创新训练项目（202111116011）Fund：Innovative Training Project (202111116011)引文格式：秦海森, 刘丽, 张凤, 等. 泡沫基材-Ni-石墨烯复合镀层制备及电催化析氢性能研究[J]. 表面技术, 2024, 53(2): 221-229.QIN Haisen, LIU Li, ZHANG Feng, et al. Preparation and Electro-catalytic Hydrogen Evolution Performance of Foam Substrate-Ni-Graphene Composite Coating[J]. Surface Technology, 2024, 53(2): 221-229.*通信作者（Corresponding author）·222·表面技术 2024年1月the electrocatalytic hydrogen evolution performance of the high coating.After graphene was embedded as the second phase coating, the surface morphology of the composite coating was obviously changed, and its existence form was granular. At a magnification of 2 000, the coating surface had a particle diameter of about1 μm. With the increase of the concentration of graphene, the particle distribution density gradually increased first and thendecreased, and the particle size became larger. The particle accumulation was the highest at the graphene concentration of 150 mg·L–1. Combined with the summary table of EDS composition analysis, it was found that with the increase of graphene concentration, the carbon content in the coating solution increased, and the C content in the composite coating gradually increased, with the highest concentration of 200 mg·L–1, and then 250 mg/L was slightly reduced. At the same time, with the increase of graphene concentration, the Ni content gradually decreased, and the Fe content was negligible. It showed that the composite coating could cover the substrate surface well and be thicker.The polarization curve and Tafel slope curve indicated that the reaction pathway of hydrogen evolution reaction (HER) with composite coating was V olmer-Heyrovsky, and the electrocatalytic adsorption step was the reaction control step. The coating prepared at 150 mg·L–1 had the lowest Tafel slope, which was 105.3 mV·dec–1. And the hydrogen evolution potential of composite coating with graphene was lower than that of coatings without graphene. At a current density of 10 mA·cm–2, the coatings prepared at 150 mg·L–1 had the lowest hydrogen evolution overpotential. AC impedance map showed that the arc resistance diameter of the Ni base graphene composite coating was less than that of the graphene-free Ni coating. Combined with the fitting data and relevant theories, the electrochemical surface area (ESCA) of the coatings joined with graphene was higher than that without graphene, and graphene increased the ESCA on the coating surface, thus improving the electrocatalytic hydrogen evolution activity of the coated electrode.In addition, the effects of coating thickness and substrate morphology on electrode electrocatalytic hydrogen evolution performance were explored. And it was found that the electrocatalytic hydrogen precipitation activity of different thickness composite coatings were basically the same. The electrocatalytic hydrogen evolution activity of foam substrate coating was significantly better than that of plate substrate coating.The timing potential test of the foam substrate-Ni-Graphene composite coating electrode at 100 mA·cm–2 constant current density showed that the initial potential of the coating electrode was about –1.48 V (vs. SCE), and the potential dropped to about –1.50 V in the first 1 000 s, the fluctuation was slightly obvious, not stable in the early stage. The fluctuation of the potential in the rest of the time was not large. The change value was only 0.01 V, and the curve was flat. It showed that the electrode electrolysis had good water stability.In conclusion, the introduction of graphene and three-dimensional porous structure of the foam substrate increase the specific surface area of the composite coating, which is the key to the good electrocatalytic hydrogen evolution activity of the electrode.KEY WORDS: electrodeposition; graphene; foam substrate; Ni base composite coating; hydrogen evolution activity随着化石能源的过度开采和使用，环境污染防治问题备受重视[1]，同时清洁能源的开发和利用受到人们的广泛关注。

石墨烯制备及其在新能源汽车锂离子电池负极材料中的应用

石墨烯制备及其在新能源汽车锂离子电池负极材料中的应用田晓鸿（西安航空职业技术学院，西安710089）摘要：新能源汽车锂离子电池对于负极材料的节能环保性要求较高，而石墨烯作为新型的碳材料，因低成本、高性能而成为新型的负极材料，而针对氧化石墨法制备流程复杂、存在污染性，且制成的微米级团聚颗粒石墨烯电化学性能受限问题，文章采用机械液相剥离的规模化制备工艺，将石墨烯与石墨复合制备成石墨烯复合材料，通过实验方法测定其作为锂离子电池负极材料的电化学应用性能，结果表明与石墨复合后，可有效优化石墨烯负极材料的使用性能，更好的满足新能源汽车发展要求。

关键词：石墨烯；负极材料；电化学性质；锂离子电池中图分类号：U469.72；TM912文献标识码：A文章编号：1001-5922（2021）01-0183-04 Preparation of Graphene and Its Application as Anode Materials for Lithium Ion Batteries of New Energy VehiclesTian Xiaohong（Xi'an Aeronautical Polytechnic Institute，Xi'an710089，China）Abstract：New energy automobile lithium-ion battery has high requirements for energy-saving and environmental protection of anode materials.Graphene,as a new carbon material,has become a new type of anode material due to its low cost and high performance.However,in view of the complicated preparation process of the graphite oxide method,the presence of pollution,and the limited electrochemical performance of the micron-sized agglomerated particles,this paper adopts the large-scale preparation process of mechanical liquid phase exfoliation to prepare graphene and graphite composites into Graphene composite material,through the experimental method to determine its electrochemical application performance as a lithium-ion battery anode material.The results show that the per⁃formance of graphene anode material can be effectively optimized after compounding with graphite,which can bet⁃ter meet the development requirements of new energy vehicles.Key words：graphene;anode material;electrochemical properties;lithium ion battery0引言随着电动汽车技术及保有量的不断发展，为实现节能减排的目的，对锂离子电池制备及使用性能提出了更高的要求。

烷基胺边缘功能化氧化石墨烯pickering乳液的摩擦学行为

表明：GO 基 Pickering 乳液比空白乳液的减摩性能好，且胺功能化 GO 在 CoCrMo 合金上比在 304 不锈钢上展现出更
优的润滑性能。对比空白乳液，在对摩擦副为 CoCrMo 合金时，GO 乳液可降低 35.9% 的平均摩擦因数和 46.7% 的钢
球磨损率，而 Oct-N-GO 乳液则可降低 48.7% 的平均摩擦因数和 73.0% 的钢球磨损率。机理分析表明，功能化 GO 良好的界面润湿性能使其所构建的 Pickering 乳液可以在金属表面形成良好的界面润滑膜；其结构中的烷基胺在摩擦过程
中更易发生剪切，降低界面剪切力而起减摩作用；同时，其所形成的润滑膜组分中含有较高的 C−O−C/C−OH 和
C=O，更好地吸附或填补到金属表面而起抗磨作用。
关键词: 氧化石墨烯；边缘功能化；界面张力；Pickering 乳液；摩擦学行为
中图分类号: TH117
文献标志码: A
文章编号: 1007−9289(2019)05–0151–09
杨红梅，李久盛，曾祥琼
(中国科学院大学中国科学院上海高等研究院，上海 200120)
摘要: 为探究氧化石墨烯 (GO) 在金属加工液领域的应用潜能，采用改进 Hummers 法合成了 GO，对其进行正辛胺
的边缘功能化修饰，并构建了基于功能化 GO 的 Pickering 乳液。研究了功能化 GO 在液-液界面的油水界面行为，以
及 GO 基 Pickering 乳液在固-液界面的摩擦学行为。利用全自动界面张力仪研究了功能化 GO 在不同油水界面的界面张力；利用 UMT-tribolab 和白光干涉仪研究了 GO 基 Pickering 乳液在 CoCrMo 合金和 304 不ro-Raman 和 XPS 分析金属摩擦副表面的润滑膜组成，以阐明 GO 基 Pickering 乳液的润滑作用机理。研究结果

石墨烯印刷油墨型红外辐射电热膜

石墨烯印刷油墨型红外辐射电热膜英文回答：Graphene, a two-dimensional material composed of carbon atoms arranged in a hexagonal lattice, has attracted significant attention in recent years due to its exceptional properties. One of its potential applicationsis in the field of infrared radiation heating, where it can be used as a heating element in various devices. To utilize graphene for this purpose, researchers have developed a graphene-based ink that can be printed onto a flexible substrate to create an infrared radiation heating film.The graphene ink used in the printing process is typically composed of graphene flakes dispersed in a solvent. The ink can be deposited onto a substrate using various printing techniques, such as inkjet printing or screen printing. Once the ink is printed, it undergoes a drying process to remove the solvent, leaving behind a thin film of graphene. This film acts as a conductive layer thatcan generate heat when an electric current is applied.The use of graphene in infrared radiation heating films offers several advantages. Firstly, graphene has excellent electrical conductivity, allowing it to efficiently convert electrical energy into heat. This makes it a highlyefficient heating element compared to traditional materials. Secondly, graphene has a large surface area, which allowsfor increased heat transfer. This means that the heatingfilm can quickly and evenly distribute heat, resulting in more efficient heating. Lastly, graphene is also highly flexible and transparent, making it ideal for applications where the heating film needs to conform to curved surfacesor be integrated into transparent devices.Infrared radiation heating films based on graphene can find a wide range of applications. For example, they can be used in the automotive industry to heat car seats ordefrost windshields. They can also be used in the construction industry to provide heating in floors or walls. Additionally, these films can be used in medical devices to provide localized heating for therapeutic purposes. Theflexibility and transparency of graphene also open up possibilities for integrating these films into wearable devices or smart textiles.中文回答：石墨烯是一种由碳原子以六角晶格排列而成的二维材料，近年来因其出色的特性引起了广泛关注。

多环芳烃典型电子性质与其大型蚤光致毒性的构效关系研究

1. 中国科学院南京土壤研究所ꎬ土壤环境与污染修复重点实验室ꎬ南京 210008
2. 中国科学院大学ꎬ北京 100049
3. 南京大学环境学院ꎬ污染控制与资源化研究国家重点实验室ꎬ南京 210023
收稿日期:2017￣01￣03 录用日期:2017￣03￣08
摘要: 多环芳烃(PAHs)是环境中广泛分布的持久性有毒有机污染物ꎬ备受研究者关注ꎮ 基于密度泛函理论(DFT)先期计算
matic hydrocarbons to Daphnia magna [J]. Asian Journal of Ecotoxicology, 2017, 12(3): 516￣525 (in Chinese)
多环芳烃典型电子性质与其大型蚤光致毒性的构效关
系研究
谷成刚1 ꎬ 朱梦荣1, 2 ꎬ 刘畅1, 2 ꎬ 提清清1, 2 ꎬ 何欢3 ꎬ 孙成3, # ꎬ 蒋新1, *
210008, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
* 通讯作者( Corresponding author) ꎬ E￣mail: jiangxin@
# 共同通讯作者(Co￣corresponding author)ꎬ E￣mail: envidean@
第3期
谷成刚等:多环芳烃典型电子性质与其大型蚤光致ｔｒａｃｔ: Polycyclic aromatic hydrocarbons (PAHs) pertain to the category list of persistent toxic substances

电子封装可靠性简介上

1. Basic understanding of atomic diffusion and diffusion related phenomena in thin films.
2. Kinetic theory of microstructure change and phase change in thin films under various driving forces. Irreversible processes will be covered.
• Kilby demonstrated 1st integrated circuit on September 12, 1958, and filed for patent in February 1959.
• Awarded Nobel Prize for Physics 2000
Figure from Jack Kilby’s US Patent 11
Electronic Thin-Film Reliability
Yingxia Liu School of Materials Science and Engineering, BIT
email: yingxia.liu@
1
The objectives of this course are to offer
1st Planar Integrated Circuit (Robert Noyce) 1961 It is thin film interconnect! (at Fairchild)
12
13
14
15
Figure from Gordon Moore’s 1965 & 1975 Paper, projecting future direction of integrated circuit