钯锰纳米多孔材料对乙醇的电催化氧化

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钯锰纳米多孔材料对乙醇的电催化氧化

钯锰纳米多孔材料对乙醇的电催化氧化陈继云;方晓婷;韩光捷;梅玲;崔荣静;韩志达【摘要】Palladium-manganese nanoporous(NP-PdMn) material was prepared by the combination of melt spinning and dealloying techniques, and charaterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy analysis (XPS), scanning electron microscope(SEM) and transmission electron microscopy (TEM). The lectrocatalytic performance of the material for ethanol oxidation was tested under the alkaline conditions. The characterization results shows that NP-PdMn is a rod-like material with three-dimensional double continuous nanoporous structure. Manganese replaces the position of partial palladium in the lattice, making the crystal spacing smaller. Some Pd and Mn exist in oxidation state on the surface of the material. Compared with the commercial Pd/C, NP-PdMn/C catalyst has better catalytic activity and stability.%采用熔体快淬结合去合金化法制备了钯锰纳米多孔材料(NP-PdMn).用X射线衍射(XRD)、X射线光电子能谱分析(XPS)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对材料进行了表征,并研究了其在碱性条件下对乙醇氧化的电催化活性.表征显示,NP-PdMn为具有三维双连续纳米多孔结构的棒状材料;锰取代了晶格中部分钯的位置使得晶面间距变小;部分钯和锰在材料表面以氧化态存在.催化性能分析表明,与商业Pd/C相比,NP-PdMn/C催化剂具有优于商业Pd/C的催化活性和稳定性.【期刊名称】《贵金属》【年(卷),期】2017(038)003【总页数】8页(P20-27)【关键词】金属材料;去合金化;钯锰纳米多孔材料(NP-PdMn);电催化性能【作者】陈继云;方晓婷;韩光捷;梅玲;崔荣静;韩志达【作者单位】常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟215500;中国矿业大学,江苏徐州221116;常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟 215500;常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟 215500;河北师范大学化学与材料科学学院,石家庄 050000;常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟 215500;河北师范大学化学与材料科学学院,石家庄 050000;常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟 215500;常熟理工学院江苏省新型功能材料重点建设实验室,江苏常熟215500【正文语种】中文【中图分类】TM911.48燃料电池，尤其是低温燃料电池如质子交换膜燃料电池(PEMFC)、直接醇类燃料电池(DEFC)和碱性燃料电池作为清洁能源，受到越来越多的关注研究[1]。

纳米钯_乙二醇体系催化Suzuki反应的研究

·94·
广州化工
2009年 37卷第 6期
2 结果与讨论
211 碱对 Suzuk i反应的影响
碱对偶联反应的影响是比较明显的。因此我们以对甲氧基溴苯和苯硼酸作为基准反应 ,以不同的碱进行 Suzuki反应 ,从中选择最合适的碱试剂。我们发现 ,该体系下 , K2 CO3、NaOH、NaH2 CO3 的效果都比较好。其他的碱试剂 ,如 K3 PO4 ·3H2O、Na3 PO4 ·12H2O、Na2 HPO4 ·12H2O ,相对产率都较低。相比之下 ,我们选择相对较廉价的 K2 CO3 作为该体系的碱试剂。
表 1 不同碱对 Suzuki反应的影响
碱
产率 / %
Na2 CO3
63
N aHCO 3
81
K2 CO3
84
KF·2H2O
39
KOH
48
N aOH
83
K3 PO4 ·3H2O
77
Na3 PO4 ·12H2O
73
Na2 HPO4 ·12H2O
72
212 温度对 Suzuk i反应的影响
考察了温度对 Suzuki反应影响。以对甲氧基溴苯和苯硼酸作为底物作为模型反应。实验结果见表 2。
表 2 不同温度对 Suzuki反应产率的影响
温度 / ℃
产率 / %
60
72
70
77
80
84
90
83
100
85
实验结果表明 , 产率随着温度上升有小幅度上升。达到 80℃之后 ,再继续升温对产率则几乎没有什么影响。反应温度为 80℃为宜。
213 催化剂用量对 Suzuk i反应的影响

钯纳米线电极的制备及其应用于乙醇的电化学氧化研究

种是多孑氧化铝（Ａ模板 ’ ＬＡＯ）。ＡＯ模板具有Ａ
耐高温、绝缘性好、制作简便、本低，成孔洞分布均
匀，而且大小可控等优点，因此，几年来模板法近制备纳米线阵列的研究多采用ＡＯ模板。Ａ钯作为一种高活性的贵金属，催化及电分在析领域已有了广泛认识和深入的研究，别是近特
第２卷第３期２
２１００年３月
化学研究与应用
ＣｈｍｉａｓａｃｎｄＡｐｉａｔｎｅｃｌＲｅｅｒｈａｐｌｃｉｏ
Ｖｏ．１２２，Ｎｏ．３Ｍａ－２ＯｌＯ１．．
文章编号：０４１５（０００．３４０１０．６６２１）３０２－４
钯纳米线电极的制备及其应用于乙醇的电化学氧化研究
张敏，程发良¨ ，志泉姚海军蔡，
（．东莞理工学院生物传感器研究中心，东１广东莞５３０；２１６
２．中山大学化学与化学化工学院，广东
广州５０７）１２５
２ＳｈｏｏＣｅｉｒａｄＣｅｉｌｎｉｅｉｇＳｎＹｔｅｎｖｒｔ，ｕｎｚｏ２５Ｃｉ）．ｃｏｌｆｈｍｓｙｎｈｍｃｇｅｒ，ｕａ— ｎＵｉｅｉＧａｇｈｕ５０７，ｈｎｔａＥｎｎｓｓｙ１ａ
ＡｂｔａｔＡｌｒｅｓａｅＰｌｄｕｎｎｗｒｒａａｉｃｌｒｗｎｔｅｓｒａｅｏｌｓｙｃｒｏｌｃｒｄｙｄｒｃｕｒｎｓｒｃ：ａｇｃｌａｌｉｍａｏｉａｒｙｗｓｄｒｔｇｏｎｏｈｕｆｃｆｇａｓａｂｎｅｅｔｅｂｉｅｔｃｒｔａｅｅｙｏｅ

乙醇在碳修饰的二氧化钛纳米管负载的钯电催化剂上的催化氧化

研究论文：８～８０４
乙醇在碳修饰的二氧化钛纳米管负载的钯电催化剂上的催化氧化
胡风平，沈培康
（山大学物理科学与工程技术学院，电材料与技术国家重点实验室，广东广州５０７）中光１２５
维普资讯
第２８卷第１期
Ｖｏ．２１８Ｎ０．１催 Nhomakorabea化
学报
２００７年１月
Ｊｎａｙ２０ａｕｒ０７
ＣｉｅｅＪｕｎｌｆＣｔｌｓｓｈｎｓｏｒａｏａａｙｉ
文章编号：０５ —８７２０） —０００２３９３（０７０１０８ —５
摘要：通过有机物分解碳化处理Ｔｉ２米管制得了Ｔｏｃ，以其为载体制备了Ｐ／ＯＣ电催化剂、察了该催化剂对碱Ｏ纳ｉ２并ｄＴｉ２，考性介质中乙醇电催化氧化的活性．果表明，化导电处理的Ｔｏｃ纳米管载体能有效改善催化剂中贵金属的分散度和电极结碳ｉ２结构，而提高催化剂的电催化活性．对催化剂活性组分的优化实验表明，ｄＴ０２从Ｐ／ｉＣ质量比为１１催化剂的活性最高．在／时１ｍｏ／ＯＨ溶液中ＰｌＬＫｄ载量均为０３ｍｇｃ的条件下，ｄＴｏ２．／ｍＰ／ｉＣ催化剂对乙醇氧化的催化活性是Ｐ／ｄＣ催化剂的３８倍．．关键词：二氧化钛；米管；钯；电催化剂；乙醇：化；燃料电池纳氧

醇类电催化氧化催化剂的研究进展

醇类电催化氧化催化剂的研究进展摘要:直接醇类燃料电池（DAFC）是以小分子醇类为燃料、直接将化学能转化为电能的装置。

它具有能量转化效率高、燃料来源丰富、储运方便、成本低廉等优点，是理想的便携式电源。

为提高碱性介质中多壁碳纳米管（MWCNT）负载 Pd 基催化剂对醇类电氧化反应的催化活性及抗中毒能力，本文采用乙二醇还原法制备了Pd/MWCNT 催化剂，并引入过渡金属进行改性，制备了 PdM/MWCNT（M = Ni、Mo、Ce）二元催化剂。

采用透射电子显微镜（TEM）、X-射线光电谱（XPS）及差热分析（DTA）等手段对催化剂的形貌、组成及结构进行表征。

以循环伏安法（CV）、线性扫描伏安法（LSV）、电化学阻抗谱（EIS）及计时电流法（CA）等电化学方法考察了催化剂在醇类电氧化反应中的催化活性及抗中毒能力。

主要研究结果如下：（1）采用乙二醇还原法制备了 Pd/MWCNT 催化剂与 PdNi/MWCNT 催化剂，结果表明添加 Ni 后的催化剂在载体表面分散更均匀，平均粒径为 2.34nm。

PdNi/MWCNT 催化剂中 Ni 主要以 Ni(OH)2和 NiOOH 形式存在，在碱性溶液中对甲醇的电催化氧化表现出较高的活性。

（2）通过 PdM/MWCNT（M=Mo、Ce）催化剂的优化实验，发现 Mo、Ce 纳米粒子的添加有助于提高催化剂的催化能力，且当 Pd:Mo=1:0.2、Pd:Ce=1:0.1 时，350℃焙烧制得的 PdMo/MWCNT、PdCe/MWCNT 催化剂分别对甲醇、乙醇的电催化氧化活性较为突出，抗 CO 中毒能力较强。

（3）通过对助催化剂钼、铈化合物的焙烧，发现随着温度的升高，金属氧化物的生成量增多，能为催化剂提供较丰富的含氧物种，促进中间产物的继续氧化，从而提高催化剂的抗中毒能力；但焙烧温度过高，会引起催化剂的导电能力下降，甚至破坏碳纳米管载体的结构，使催化剂失效。

Abstrac t: the direct alcohol fuel cell (DAFC) is a device which can convert chemical energy into electrical energy by the small molecule alcohol as fuel.. It has the advantages of high energy conversion efficiency, rich fuel source, convenient transportation, low cost, etc., is the ideal portable power source. In order to improve the alkaline medium multiwalled carbon nanotubes (MWCNTs) load Pd based catalyst for alcohol electro oxidation reaction catalytic activity and anti poisoning ability. This paper using ethylene glycol reduction method for preparing the Pd/MWCNT catalyst, and the introduction of transition metal modified PdM/MWCNT (M = Ni, Mo, CE) binary catalyst was prepared. The morphology, structure and structure of the catalysts were characterized by transmission electron microscopy (TEM), X- ray photoelectron (XPS) and differential thermal analysis (DTA).. By cyclic voltammetry (CV) and linear sweep voltammetry (LSV), electrochemical impedance spectrum (EIS) and timing current method (CA) and electrochemical methods to study the catalytic activity of the catalysts in the methanol electro oxidation reaction and anti poisoning ability. The main results are as follows:(1) using ethylene glycol reduction method to prepare Pd/MWCNT catalyst andPdNi/MWCNT catalyst. The results show that after adding Ni catalyst on the surface of the carrier dispersed more evenly, the average particle size of 2.34nm. The PdNi/MWCNT catalyst of Ni mainly exists in the presence of Ni (OH) 2 and NiOOH, and shows higher activity of Electrocatalytic Oxidation for methanol in alkaline solution..(2) by PdM/MWCNT (M = Mo, CE) catalyst optimization experiment. It was found that the Mo, CE nanoparticles add help to improve the catalytic activity of the catalyst and when Pd:Mo=1:0.2 Pd:Ce=1:0.1, 350 DEG C roasting PdMo/MWCNT, PdCe/MWCNT catalyst respectively electrocatalytic activity for methanol, ethanol is more prominent, the resistance to CO poisoning ability.(3) by roasting of molybdenum catalyst, cerium compounds, discovered in the production of metal oxide increased with the increase of temperature, catalyst provides abundant oxygenated species, promote intermediates to oxidation, so as to improve the catalyst anti poisoning ability; but calcination temperature is too high will cause catalyst conductivity decreased, and destruction of the structure of carbon nanotube carrier, the catalyst failure.关键词：直接醇类燃料电池；阳极催化剂；活性；抗中毒；钯、电、核能Keywords: direct alcohol fuel cell; anodic catalyst; activity; poisoning; PD, electric, nuclear energy.1.2 燃料电池的概述燃料电池（Fuel Cell）是等温地将燃料和氧化剂中的化学能直接转化为电能的一种电化学的发电装置。

钯纳米线的制备及其在乙醇燃料电池中的应用

中图分类号：Ｑ５．１Ｔ００４
文献标识码：Ａ
文章编号：８２１１（００）４０１－３１１— ９８２１０－０３０
０引言
直接醇类燃料电池由于燃料不用经过重整而直接用于发电因而具有高理论比能量密度和极高的发电效率。近年来，直接乙醇燃料电池（ＥＤ —
关键词：醇类燃料电池；；米线钯纳
ＰａｌｄｉｎｏｒｓａｌａｕｍＮａｗｉｅｎｄＡｐｐｌｃｔｏｎｉｈａｌＦｕｌＣｅｌｉａｉｎＣｔｎｏｅｌ
ＤＡＩＸｉｎ — ｈｎａｇ— ｅｇｃ
（ｏｌｇｆｈｍｉｒｎｈｍｃｌｎｉｅｒｇＨｆ２０３，ＣｉａＣｌｅｏｅｓｙａｄＣｅｉａＥｇｎｅｉ，ｅｅ３０９ｅＣｔｎｉｈｎ）
ｃ，ｈｅｋｉｖｒｈｒｓｏｓｔａｓｖｌｇｎｒａｅ，ｈｌｏｏｎｅｅｔｄｕｆｃａａｉｌｏｓｍｅｎｍＴｅｐａｓｅｙｓａｐ，ｈｗｈｔａｏｔｅｉｃｅｓｓｔｅａｃｈｌｏｌｃｒｅｓｒａｅｗｓｒｐｄｙｃｎｕｄａｄａｏ
第７卷第４期２１００年８月
纳
米
科
技
Ｎｏ．４
Ｎａｏｓｉｎｃ＆Ｎａｎｔｃｎｃｅｅｏｅｈｎｏｏｙｌｇ
Ａｕｕｓ２０１ｇｔ０
钯纳米线的制备及其在乙醇燃料电池中的应用

超薄金修饰的钯电极用于乙醇安培传感研究

超薄金修饰的钯电极用于乙醇安培传感研究doi:10.3969/j.issn.1674-7100.2019.03.007收稿日期：2019-02-25基金项目：湖南省教育厅基金资助项目（18C0529）作者简介：巢龙（1989-），男，湖南长沙人，湖南工业大学讲师，博士，主要从事电催化和电分析化学方面的研究， E-mail ：chaolong4617@通信作者：黄钊（1984-），男，湖南常德人，湖南工业大学讲师，博士，主要从事电催化和电分析化学方面的研究， E-mail ：huang1020@巢龙1, 2 黄钊11.湖南工业大学生物医用纳米材料与器件湖南省重点实验室湖南株洲 4120072. 湖南师范大学化学生物学及中药分析教育部重点实验室湖南长沙 410081摘　要：超薄贵金属膜具有独特的结构和功能，创新其制备方法，拓展其电化学应用具有重要意义。

通过在镀Pd 的玻碳电极（GCE ）上电沉积欠导电Se 超薄膜并作为模板，再与HAuCl 4进行原电池置换反应，制备了超薄Au 膜修饰的镀Pd 电极（Au Se /Pd/GCE ），并在碱性条件下采用循环伏安法研究了Au Se /Pd/GCE 对乙醇的电催化氧化性能影响，并构建了乙醇安培传感器。

研究表明，与裸Pd 电极相比，Au Se /Pd/GCE 对乙醇的电催化氧化活性更高；在最优条件下，修饰电极对乙醇的线性检测范围为0.025~10.000 mmol·L -1，灵敏度为0.94 (mA·cm -2)/(mmol·L -1)，优于多数已报道的方法。

此种以欠导电物质均匀电沉积薄膜为模板，采用原电池置换反应制备超薄贵金属膜的新方法有望在纳米电催化剂的制备及电催化与电分析研究中广泛应用。

关键词：超薄膜；欠导电材料；贵金属；安培传感；乙醇检测中图分类号：O657.1；O646.51 文献标志码：A文章编号：1674-7100(2019)03-0044-08引文格式：巢龙，黄钊. 超薄金修饰的钯电极用于乙醇安培传感研究[J]. 包装学报，2019，11(3)：44-51.1 研究背景乙醇是一种常见的小分子有机化合物，在食品工业、医药卫生、燃料电池、工农业生产中具有广泛的研究与应用。

一种利用乙醇还原制备纳米钯电催化剂的方法[发明专利]

(10)申请公布号 CN 102872861 A(43)申请公布日 2013.01.16C N 102872861 A*CN102872861A*(21)申请号 201210403693.X(22)申请日 2012.10.22B01J 23/44(2006.01)B01J 37/03(2006.01)B22F 9/24(2006.01)(71)申请人安徽理工大学地址232001 安徽省淮南市田家庵区学院路(72)发明人王艳丽谭德新张明旭彭勇军刘永峰晏莹张雪萍(74)专利代理机构合肥天明专利事务所 34115代理人奚华保(54)发明名称一种利用乙醇还原制备纳米钯电催化剂的方法(57)摘要本发明涉及一种利用乙醇还原制备纳米钯电催化剂的方法，借助乙醇的还原作用和助溶剂作用将氯化钯（PdCl 2）还原为金属钯（Pd ）纳米粒子，首先配置乙醇水溶液；然后将PdCl 2粉末和保护剂加入至乙醇溶液中，通保护气并加热搅拌，使钯阳离子发生还原反应得到Pd 纳米粒子；反应完毕后离心分离得到黑色沉淀，使用乙醇、丙酮洗涤后干燥，即得纳米钯电催化剂。

本发明采用乙醇水溶液作为溶剂，利用乙醇的还原作用和溶剂作用，没有额外添加诸如抗坏血酸等化学还原剂，并借助磁力搅拌和水浴加热确保了PdCl 2的溶解性，在常压环境一步合成纳米钯电催化剂，成本低廉，环境友好，操作过程简便易行，所制得的纳米钯电催化剂产率高且粒径分布集中，具有较好的应用前景。

(51)Int.Cl.权利要求书1页说明书5页附图2页(19)中华人民共和国国家知识产权局(12)发明专利申请权利要求书 1 页说明书 5 页附图 2 页1/1页1.一种利用乙醇还原制备纳米钯电催化剂的方法，其特征在于：利用乙醇为还原剂，将氯化钯还原为金属钯纳米粒子，其制备步骤为：（1）配置乙醇水溶液；（2）将氯化钯粉末和保护剂加入至乙醇水溶液中配制成混合溶液，将配好的混合溶液于23-28℃搅拌5-10min ，溶液颜色为浅黄色；（3）通保护气并加热搅拌，得到黑色悬浮液，停止反应；（4）反应完毕后离心分离得到黑色沉淀，使用乙醇、丙酮洗涤后真空干燥即得纳米钯电催化剂。

一种用于甲醇、乙醇及异丙醇燃料电池的钯金属纳米粒子催化材料、

专利名称：一种用于甲醇、乙醇及异丙醇燃料电池的钯金属纳米粒子催化材料、其制备方法及应用
专利类型：发明专利
发明人：李琴,周丹丹,潘林娜,崔皓,安浩,翟建平
申请号：CN201210521994.2
申请日：20121207
公开号：CN102945971A
公开日：
20130227
专利内容由知识产权出版社提供
摘要：本发明公开了一种用于碱性条件下甲醇、乙醇和异丙醇燃料电池的钯金属纳米粒子催化材料、制备方法及应用。

该材料以多壁碳纳米管作为基底，以二氧化钛作为中间载体，5~8纳米的钯金属粒子均匀的分布在二氧化钛颗粒表面。

制备过程为：首先对二氧化钛和碳纳米管进行预处理，利用原位合成法对二氧化钛和碳纳米管进行合成，得到二氧化钛-碳纳米管复合载体材料；然后将复合材料分散于氯化钯的水溶液中，添加还原剂硼氢化钠，将钯纳米颗粒均匀地负载到复合载体上，制得改性钯/二氧化钛-碳纳米管催化材料。

本发明在碱性条件下具有高催化活性、高稳定性及高抗毒性，能有效降低催化剂中毒。

本发明工艺条件温和，工艺简单，催化材料稳定性及重复性较好。

申请人：南京大学
地址：210000 江苏省南京市栖霞区仙林大道163号南京大学环境学院
国籍：CN
代理机构：江苏圣典律师事务所
代理人：贺翔
更多信息请下载全文后查看。

乙醇电催化氧化研究现状

乙醇电催化氧化研究现状
随着人们对污染环境和保护环境的越来越重视，乙醇电催化氧化成为当今研究领域之一，
得到了非常多的关注。

首先，乙醇电催化氧化技术可以有效转化乙醇，使之发挥最大的用途，减少乙醇的排放量。

其次，乙醇电催化氧化可以有效降低乙醇对周围环境的影响，更好地保护环境。

此外，乙
醇电催化氧化也可以降低乙醇的污染指数，消除乙醇的恶臭，改善空气质量，使乙醇更安全、更有效的利用。

最近，许多学者研究了乙醇电催化氧化体系及其相关反应机理。

在传统催化剂的基础上，
逐步完善了金属、配体、活性物质，并将它们应用到多相催化氧化反应之中，从而提高乙
醇催化氧化的稳定性、避免污染物的挥发等。

总而言之，乙醇电催化氧化是一种新兴的、绿色、无污染的技术，它可以降低乙醇的污染
指数和消除乙醇的恶臭，从而对环境、人类健康产生重要的保护作用。

由于这一技术正在
发展，因此，乙醇电催化氧化技术的研究和开发还有很多空间，研究者们将继续努力开发
更多更新的技术来改善空气质量和减少乙醇的污染。

碳纳米管上原位沉积钯-钴-镍纳米颗粒及其对乙醇氧化的电活性

碳纳米管上原位沉积钯-钴-镍纳米颗粒及其对乙醇氧化的电活性陈清华;易清风;阳铮;周秀林;刘小平;聂会东;徐国荣【摘要】以水合肼为还原剂,在水和乙醇的混合溶液中制备多壁碳纳米管(MWCNT)负载的纳米镍(Ni/MWCNT)和纳米镍钴(Ni-Co/MWCNT)颗粒,然后将它们分别与氯化钯溶液反应,形成的钯纳米颗粒原位沉积在MWCNT表面,从而得到MWCNT 负载的Pd-Ni/MWCNT和Pd-Ni-Co/MWCNT催化剂.SEM和TEM图像显示,MWCNT上的催化剂颗粒是由5～10 nm的小颗粒团聚而成的30～100 nm的大颗粒,三金属催化剂的粒径比双金属的粒径小,在MWCNT上的分散度更高.ICP和EDS分析显示,Pd直接还原并包覆在纳米镍和纳米镍钴表面;采用循环伏安和计时电流技术,研究了催化剂在碱性溶液中对乙醇氧化的电催化活性,结果表明.Pd-Ni-Co/MWCNT催化剂对乙醇氧化具有强的电催化活性,乙醇氧化对应的峰电流密度达101.8 mA·cm-2,并且催化剂催化活性稳定.【期刊名称】《无机化学学报》【年(卷),期】2016(032)007【总页数】9页(P1161-1169)【关键词】钯催化剂;乙醇氧化;镍纳米颗粒;燃料电池;原位还原【作者】陈清华;易清风;阳铮;周秀林;刘小平;聂会东;徐国荣【作者单位】湖南科技大学化学化工学院,湘潭411201;湖南科技大学化学化工学院,湘潭411201;理论有机化学与功能分子教育部重点实验室,湘潭411201;湖南科技大学化学化工学院,湘潭411201;湖南科技大学化学化工学院,湘潭411201;湖南科技大学化学化工学院,湘潭411201;湖南科技大学化学化工学院,湘潭411201;湖南科技大学化学化工学院,湘潭411201【正文语种】中文【中图分类】O614.82+3直接醇燃料电池具有能量密度高、燃料易存储且安全、低毒等优点，受到各国科学家广泛研究。

电沉积制备钯铂电极上乙醇的电催化氧化

电沉积制备钯铂电极上乙醇的电催化氧化
佘沛亮;姚士冰;周绍民
【期刊名称】《物理化学学报》
【年(卷),期】2000(016)001
【摘要】研究了乙醇在碱性介质(1.0mol·L-1NaOH)中电沉积制备的Pd/GC、Pt/GC和Pd-Pt/GC电极上的电催化氧化.实验结果表明:由此法制备的钯铂系列合金电极对乙醇的电催化氧化表现出明显的协同效应--乙醇在含钯原子分数
yPd=0.336的Pd-Pt/GC合金电极上的阳极交换电流密度是其在纯铂电极上的30多倍.
【总页数】5页(P22-26)
【作者】佘沛亮;姚士冰;周绍民
【作者单位】厦门大学化学系,厦门361005;厦门大学化学系,厦门361005;厦门大学固体表面物理化学国家重点实验室,厦门361005
【正文语种】中文
【中图分类】O64
【相关文献】
1.乙醇在碳修饰的二氧化钛纳米管负载的钯电催化剂上的催化氧化 [J], 胡风平;沈培康
2.甲醇在有序化氰桥混配物修饰铂电极上的电催化氧化 [J], 马永钧;刘婧;何春晓;李婷婷;周敏;李琼琳
3.碳纳米管上电沉积钯对乙醇的电催化氧化研究 [J], 文颖;李燕;林嫒璟n;杨海峰;
许东芳
4.甲醛在聚苯胺载铂电极上的电催化氧化 [J], 陈忠平;褚道葆;秦家成;宋常春;汪徐春;陈君华;过家好;张婷
5.聚苯胺载铂电极对乙醇的电催化氧化 [J], 武克忠;王新东;张超星;刘晓地;赵娜;韩铁城
因版权原因，仅展示原文概要，查看原文内容请购买。

钯基氧还原和乙醇氧化反应电催化剂:关于结构和机理研究的一些近期见解

钯基氧还原和乙醇氧化反应电催化剂：关于结构和机理研究的
一些近期见解
吴志鹏;钟传建
【期刊名称】《电化学》
【年(卷),期】2021(27)2
【摘要】质子交换膜燃料电池和直接乙醇燃料电池已成为可持续性清洁能源研究的一个聚焦点。

在燃料电池中,氧还原反应和乙醇氧化反应是两个重要的反应,其相关高活性、高稳定性并且廉价的催化剂的研发仍然存在很多问题,极大地制约了燃料电池的大规模商业化应用。

其中的挑战主要来自于对纳米催化剂结构和反应机理的有限认识。

由于实验表征理论计算的结合,对钯基合金纳米材料电催化剂的研究得到了很大的进展。

本文从实验和理论计算两个方面出发,重点讨论了应用于氧还原反应和乙醇氧化反应的钯和钯基电催化剂的结构和反应机理方面的近期研究的一些见解。

这些见解对未来催化剂的设计与优化有一定的启发意义。

【总页数】13页(P144-156)
【关键词】氧还原反应;乙醇氧化反应;电催化剂;相态结构;反应机理;燃料电池
【作者】吴志鹏;钟传建
【作者单位】郑州大学化学学院绿色催化中心;纽约州立大学宾汉姆顿分校化学系;南洋理工大学化学与生物医学工程学院
【正文语种】中文
【中图分类】TM9
【相关文献】
1.钛基纳米多孔钯-铜催化剂的水热法合成及对甲酸氧化和氧还原的电活性
2.富氧条件下钯催化剂上氢气还原氧化氮微观反应动力学研究
3.无氧条件下钯催化剂上氢气还原氧化氮的微观反应动力学研究
4.钛基纳米多孔钯-铜催化剂的水热法合成及对甲酸氧化和氧还原的电活性（英文）
5.钯催化剂对锂空气电池氧析出和氧还原反应的催化机理的研究
因版权原因，仅展示原文概要，查看原文内容请购买。

Pd-Ag合金纳米线的可见光辅助简易合成及其对乙醇的电催化氧化

Pd-Ag合金纳米线的可见光辅助简易合成及其对乙醇的电催化氧化谭德新;王艳丽【摘要】Using palladium nitrate and silver nitrate as the metal precursor,ethanol and sodium citrate tribasic dehydrate as reducing agents and poly (vinyl pyrrolidone) (PVP) as a stabilizer and guiding agent,Pd-Ag alloy nanowires were synthesized via visible-light-assisted solution approach with a commercial incandescent lamp as light source.The morphologies,crystal structure and optical properties were characterized by field emission scanning electron microscopy (FESEM),transmission electron microscopy (TEM),high resolution transmission electron microscopy (HRTEM),power X-ray diffraction (PXRD),and UV-visible spectroscopy,respectively.The electrocatalytic properties of the Pd-Ag alloy nanowires modified glassy carbon electrode for ethanol oxidation were investigated by cyclic voltammetry and chronoamperometry.The Pd-Ag alloy nanowires exhibited much better electrocatalytic performance than Pd nanoparticles toward ethanol oxidation reaction in alkaline media in terms of the electrocatalytic activity,anti-poisoning ability and stability.%以硝酸钯和硝酸银为金属前驱体,乙醇和柠檬酸钠作为还原剂,聚乙烯吡咯烷酮作为稳定剂和导向剂,以普通市售白炽灯作为光源,采用简易可见光辅助液相法合成了Pd-Ag合金纳米线.通过FESEM、TEM、HRTEM、PXRD和UV-Vis等技术对样品的形貌、晶体结构和光学性质进行了表征,并通过循环伏安法和计时电流法研究了Pd-Ag合金纳米线修饰玻碳电极对乙醇的电催化氧化.与相同条件下制备的纳米钯材料相比,Pd-Ag合金纳米线具有更好的电催化活性、抗中毒性和稳定性.【期刊名称】《无机化学学报》【年(卷),期】2018(034)004【总页数】7页(P777-783)【关键词】Pd-Ag合金;纳米线;可见光;乙醇;电催化【作者】谭德新;王艳丽【作者单位】岭南师范学院化学化工学院,湛江524048;岭南师范学院化学化工学院,湛江524048【正文语种】中文【中图分类】O6140 IntroductionDirect liquid fuel cells,especially direct ethanol fuel cells (DEFCs),is considered to be one of the promising clean energy sources with high energy conversion efficiency and low environmental pollution[1-2].Up to now,designing highly efficient catalysts is still the main challenges for DEFCs applications.Pd-based catalysts,because of their low cost and good tolerance to the poisoning caused by intermediate species during the ethanol oxidation process,are likely to be put into practical use for DEFCs[3].Particularly,the incorporation of a second metal (M)into Pd forforming PdM alloy often brings superior catalytic performance,due to the synergistic effects and rich diversity of the compositions[4].Recently,several PdM catalysts,such as Pd-Ag[3],Pd-Cu[5]and Pd-Sn[6],demonstrate the enhanced catalytic activity toward the ethanol oxidation reaction (EOR).For example,welldispersed fcc-Pd-Cu alloys are successfully prepared by one-pot synthesis and a two-step reductive process,and show an excellent catalytic activity,durability and catalytic stability toward EOR[5].On the other hand,specific structures,such as one-dimensional(1D)bimetallic nanowires or nanotubes[7],threedimensional(3D)noble metal networks (NWs)[3],nanoflowers[8],nanoneedles[9],or core-shells[10],have significant effects on the properties of the materials.Among them,1D bimetallic nanowires exhibit enhanced electrocatalytic activity for fuels anodic oxidation and oxygen cathodic reduction owing to the large specific interface areas.Recently,Chen et al.[2]synthesized bimetallic Pd-Ag alloy nanowires at 170℃with oil bath by one-step wet chemicalstrategy,exhibiting enhanced catalytic activity for formic acid pared to the conventional heat treatment methods,the products are more uniform and the growth mechanism can be more conveniently resolved using photochemical and irradiation synthesis methods[11-13].These simple processes have proven to be a promising route for the preparation of Pd-based catalysts.Current photochemical methods focus mainly on the use of high-energy radiation,such as UV light orγ-irradiation.For instance,Nenoff et al.[14]have successfully prepared Ag-Ni alloy nanoparticles and Pd-Ni alloy nanoparticles via a 60Co-γsource.Pande et al.[15]have reported the synthesis of monometallic (Au and Pd)and bimetallic(AuPd)nanoparticles using graphitic carbon nitride quantum dots under the UV lamp(λ=365 nm).Therefore,it is important to design a safer,cheaper,and more facile light-assisted method to synthesize 1D Pd-based alloy nanostructures.Recently,we have presented a novel visible-light-assisted method to synthesize Pd nanoparticles with single-crystalline and multiple-twinned structures[16-17].However,to the best of our knowledge,there have been few reports on visible light-assisted synthesis of Pd-based alloy,especially with 1D nanowiresstructures.Thus,we have geared our efforts towards exploring asimple,inexpensive,and efficient approach to the large-scale fabrication of 1D Pd-based alloy nanostructures.In this paper,a facile and environmentally friendly visible-light-assisted method has been developed for the synthesis of 1D Pd-Ag alloy nanowires under the irradiation of visible light from a commercial incandescent lamp.The unique nanowires were produced by the coreduction of Pd and Ag precursors in the presence of sodium citrate tribasic dehydrate and poly (vinyl pyrrolidone).The as-prepared Pd-Ag nanowires exhibited excellent electrocatalytic activity toward EOR.1 Experimental1.1 Chemicals and materialsPalladium nitrate (Pd(NO3)2·2H2O, ＞99.9%),silver nitrate(AgNO3,＞99.8%)and poly(vinyl pyrrolidone)(PVP,M W=58 000)were purchased from Sinopharm Chemical Reagent Co.,Ltd.Sodium citrate tribasic dehydrate(Na3C6H5O7·2H2O, ＞99%)and ethanol were obtained from Nanjing Chemical Reagent No.1 Factory.All other chemicals were analysis reagent(AR)grade and used as received.1.2 Synthesis of Pd-Ag alloy nanowiresIn a typical synthesis,sodium citrate tribasic dehydrate(3.4 mmol),PVP(1.7 mmol),Pd(NO3)2·2H2O(26.27 mmol)and AgNO3(30.61 mmol)was mixed with 20 mL of ethanol and 4 mL of deionized water in a glass vessel.The mixture was dispersed to form a homogeneous solution by constant strong stirring for 10 min at room temperature.Then,the mixture was irradiated under constant stirring for 2 h with visible light from the 200-Watt incandescent lamp at a distance of 5 cm (5.30 mW·cm2 put on the reacting mixture).Two hours later,the temperature of mixture was 78℃.The color of solution was gradually changed from pale yellow to dark.The dark suspensions were precipitated by acetone and washed at least three times with ethanol to remove excess metal precursors and PVP.The final dark product could be easily redispersed in ethanol solvents to yield a clear homogeneous solution.As a comparison,Pd and Ag nanomaterials were synthesized using the same method.The final products were denoted as Pd,Ag and Pd-Ag,respectively,according to the different compositions. 1.3 CharacterizationTransmission electron microscopy(TEM)images,high resolution transmission electron microscopy(HRTEM)images,selected area electron diffraction(SAED)patterns and energy dispersive spectrometer(EDS)were carried out on a JEM-2010 instrument operated at 200 kV.Field emissionscanning electron microscopy (FESEM)images were performed with a Sirion 200 instrument.Powder X-ray diffraction(PXRD)pattern was recorded on a XD-3 type X-ray diffractometer employing Cu Kα radiation(λ=0.154 06 nm)for scattering angles 25°≤2θ≤90°with 36 kV and 30 mA.UV-visible spectroscopy of the prepared suspensions was obtained by an UV-visible spectrophotometer (UV-2600)from Shimadzu with quartz cuvettes.The intensity of the light was detected by a FZ400 visible light power meter. 1.4 Electrochemistry testsElectrochemical measurements were performed with a CHI 660E electrochemical workstation(CH Instruments,ChenhuaCo.,Shanghai,China)at room temperature,and conducted on a conventional threeelectrode cell,which includes a platinum wire as counter electrode,a saturated calomel electrode(SCE)as reference electrode and the nanomaterials-modified glassy carbon electrode (GCE,3 mm in diameter)as working electrode.In all electrochemical measurements,the current densities were normalized to the geometric surface area of the GCE.For the preparation of the nanomaterials modified electrode,6μL of a suspensi on containing nanomaterials (nanomaterials concentration=1 g·L-1)was dropped on the clean electrode surface (the area of theelectrode=7.065×10-2 cm2)and dried in air.Next,the Nafion film was prepared by dropping 3μL of a Nafion solution (0.1%,w/w)onto the electrode and allowed the solvent to evaporate at room temperature.The solutions were deaerated thoroughly for at least 30 min with pure nitrogen gas and kept under a positive pressure of this gas during theexperiments.All experiments were performed at room temperature.2 Results and discussion2.1 Characterization of Pd-Ag alloy nanowiresThe crystalline phase of the Pd-Ag alloy nanowires was further studied with PXRD measurement as shown in Fig.1.For comparison,the PXRD patterns of Pd and Ag are also displayed in Fig.1.In the pattern of Pd,the peaks at ca.40.01°,46.52°,68.11°,82.00°and 86.40°represent thePd(111),Pd(200),Pd(220),Pd(311)and Pd(222)planes,pared to the data of Pd,the diffraction peaks from Pd-Ag nanowires shift to lower 2θva lues,suggesting the reduction in lattice constant.Here,all the diffraction peaks from Pd-Ag nanowires locate between the positions expected for the Pd and Ag,indicating the obvious alloying of Pd and Ag.Such PXRD phenomenon has also been observed with other bimetallic alloy nanostructures[2-3].Moreover,neither a Pd nor an Ag single component peak was detected,confirming the presence of only single-phase Pd-Ag alloys.It also should be noted that,from the PXRD pattern of Pd-Ag,the intensity ratio between the diffraction peaks of Pd(111)andPd(200)is 2.13,suggesting the abundant (111)planes of the Pd-Ag nanowires.The bimetallic Pd-Ag nanoparticles′size can be calculated according to Scherrer equation[18]:Fig.1 PXRD patterns of Pd,Ag and Pd-Ag alloy nanowireswhere L is the size of Pd-Ag nanoparticles.λKα1 is the X-ray wavelength (λ=0.154 nm).B2θ is the half-peak width.θmax is the Bragg angle.Thecalculated nanoparticle size of Pd-Ag nanowires is 4.89 nm,which agree with the TEM results very well.The morphologies of the as-synthesized materials were characterized by FESEM(Fig.2(A))and TEM(Fig.2(B,C))measurements,which confirms the formation of the nanowires by a facile visible-light-assisted method.It can be seen that,uniform nanowires with high yield were obtained.The length of such nanowires can reach up to 250 nm with average diameters of 4 nm.For a single nanowire,it consists of interconnected nanoparticles(top left inset in Fig.2(C)).To investigate the crystal structures of the synthesized Pd-Ag nanowires,HRTEM analyses were also performed(Fig.2(D)).Well-resolved lattice fringes can be seen in Fig.2(D).PXRD result is consistent with(111)interplanar spacing found in the HRTEM measurements.By careful measurements,it was found that there is mainly one type of lattice fringes with interplanar spacing of 0.23 nm,which is ascribed to the (111)lattice plane of the Pd-Ag alloy nanostructure.The lattice fringes are not continuous and their orientations vary,demonstrating that the interconnected Pd-Ag nanowires are polycrystalline.This is further confirmed by the selected area electron diffraction(SAED)pattern,as shown in Fig.2(B),inset.The morphology of such ultrathin nanowires is very similar to that of other two-step synthesized Pd-Pt[19]and one-step synthesized Pd-A g nanowires at 170℃with polyol reduction method[2].So the present report provides a facile route for preparing bimetallic alloy nanowires.From EDSanalysis shown in Fig.2(E),both Pd and Ag are present in the nanowire materials in addition to the Cu substrate.The average molar ratio of Pd toAg is determined to be 46∶54 based on the EDX measurement,which is close to 26.27∶30.61.It is clear that the precursors can be largely reduced in the presence of sodium citrate tribasic dehydrate and ethanol[3].Fig.2 (A)FESEM image,(B)TEM image and the corresponding SAED pattern(inset),(C)high-magnification TEM image,(D)HRTEMimage,and(E)EDX spectrum of Pd-Ag alloy nanowiresFig.3 UV-visible spectroscopy of Pd,Ag and Pd-Ag alloy nanowiresFig.3 shows the UV-Vis absorption spectra of Ag,Pd-Ag and Pd nanoparticles in colloid state.In Fig.3,a distinct band is observed at 411 nm for Ag colloid that must be due to the localized surface plasmon resonance (SPR)excitation of the Ag nanoparticles[20].It is noteworthy that this band is gradually weakened,with a clear red-shift,as Pd is added to form Pd-Ag alloy,and no UV-Vis absorption is seen at all for pure Pd colloid.The UV-Vis absorption characteristics here also agree well with the Pd-Ag alloy reported previously,indicating Pd-Ag nanoparticles are present in a form of homogeneous alloy[20-21].2.2 Ethanol oxidation with Pd-Ag alloy nanowiresThe electrocatalytic activities of Pd nanoparticles and Pd-Ag nanowires were studied by cyclic voltammetry (CV)from-0.8 to 0.3 V with the same Pd loading.Fig.4(A)shows the typical CV curves of Pd and Pd-Ag nanowires in N2-saturated 1 mol·L-1 KOH solution.Both samples present reduction peaks of palladium oxides between-0.60 and-0.20 V in the negative scan.Pd-Ag alloy present the highest reduction peak.In the positive scan,OH-was adsorbed onto the surface of catalysts.In comparison with Pdnanoparticles,Pd-Ag alloy shows a more negative onsetpotential,indicating the easier adsorption of OH-on the surface[3]. According to the CV curves in Fig.4(A),the corresponding ECSA of each catalyst was calculated by quantification of the electric charges associated with the reduction of PdO[22],as shown in the following equation[4]:where Q is the charge for PdO reduction on the surface,which can be obtained from the area integral of Fig.4(A).m is the mass of Pd(6μg).C is the charge required to reduce the layer of PdO(420 μC·cm-2).v is the scan rate,which is 50 mV·s-1.The calculated ECSA is listed in Table 1.It has been demonstrated that ECSA dominates the electrocatalytic activity of catalyst materials.Higher ECSA contributes to an increase of ethanol oxidation reaction activity and thus an increase of the overall fuel cell performance[23].The specific ECSA of the Pd-Ag alloy nanowires(71.43m2·gPd-1)is highe r than the Pd nanoparticles(37.57 m2·gPd-1).Fig.4 CV curves of Pd and Pd-Ag catalysts in N2-saturated 1 mol·L-1 KOH(A)and 1 mol·L-1 KOH+1 mol·L-1 CH3CH2OH solution(B)at a scan rate of 50 mV·s-1Table 1 Electrochemical parameters of Pd and Pd-Ag alloynano wiresMaterial Onset potential/V Peak current/(A·mgPd-1) I f/I b ECSA/(m2·gPd-1)Pd -0.56 15.42 1.26 37.57 Pd-Ag -0.66 42.93 1.43 71.43 Fig.4(B)shows the second voltammogram run with Pd nanoparticles and Pd-Ag nanowires modified electrode in 1 mol·L-1 KOH co ntaining 1 mol·L-1 ethanol,respectively.Both samples display a typical current peak in theforward scan,representing the oxidation of ethanol.The onset potential and peak current of Pd and Pd-Ag catalysts are summarized in Table 1.A more negative onset potential and higher peak current were presented on Pd-Ag alloy nanowires compared to Pd nanoparticles.In the backward scan,another oxidation peak is formed on the two CV curves,which is associated with the oxidation of intermediates of ethanol dissociativea dsorption.The accumulation of these intermediateswill cause“catalyst poisoning”[24-25].The ratio of forward peak current density (I f)to backward peak current density (I b)is used to evaluate the catalyst tolerance to carbonaceous intermediates accumulation[26].The ethanol oxidation reaction test results show that the I f/Ib values of the synthesized Pd-Ag alloy nanowires are larger than that of Pd,indicating the better tolerance to carbonaceous intermediates accumulation of as-prepared nanowires.The CV curves of the ethanol oxidation reaction on the Pd-Ag alloy nanowires catalyst in 1.0 mol·L-1 KOH containing 1.0 mol·L-1 ethanol at different scan rates is shown in Fig.5(A),and the insert shows the relationship between the peak current density and the square root of scan rate.As can be seen,the peak current densities are linearly proportional to the square root of the scan rates,suggesting that the ethanol oxidation reaction on the Pd-Ag nanowires catalyst in alkaline media may be controlled by a diffusion process[27-28].To investigate the electrocatalyst stability of Pd nanoparticles and Pd-Ag alloy nanowires,chronoamperometric tests were carried out on thecatalysts at a potential of-0.3 V for 2 000 s in N2-saturated 1 mol·L-1 KOH+1 mol·L-1 CH3CH2OH solution,as shown in Fig.5(B).Both the catalysts show a significant decay at the very beginning and then remain stable.The current decay of the EOR implies the formation of carbonaceous intermediates,which can poison the active sites of the catalysts.As expected,the Pd-Ag alloy nanowires show higher current density at the start and the end of the tests than Pd nanoparticles,indicating its better catalytic activity and stability against the poisoning[25,29].Fig.5 (A)CV curves of the Pd-Ag alloy nanowires with the various scan rates,and the insert is the dependence of cathodic peak current density on the square root of scan rate;(B)Chronoamperometric curves of Pd and Pd-Ag alloy nanowires at an electrode potential of-0.3 V3 ConclusionsIn summary,we have synthesized Pd-Ag alloy nanowires via a facile visible-light-assisted method.In cyclic voltammetric and chronoamperometric tests of ethanol oxidation,Pd-Ag alloy nanowires present much better catalytic activity with larger oxidation current density,higher ECSA,more negative onset potential,and better stability in comparsion with Pd nanoparticles.Overall,the present study not only provides a facile one-step method to prepare alloy nanowires, but also find the obtained Pd-Ag electrocatalyst with high catalytic performance for application in fuel cells. 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2017年8月贵金属 Aug. 2017第38卷第3期Precious MetalsV ol.38, No.3收稿日期：2016-10-18基金项目：国家自然科学基金(51371004)。

第一作者：陈继云，男，硕士研究生，研究方向：燃料电池催化剂。

E-mail ：1176621304@ *通讯作者：韩志达，男，博士，教授，研究方向：磁性材料。

E-mail ：han@钯锰纳米多孔材料对乙醇的电催化氧化陈继云1, 2，方晓婷1，韩光捷1, 3，梅玲1, 3，崔荣静1，韩志达1 *(1. 常熟理工学院江苏省新型功能材料重点建设实验室，江苏常熟 215500； 2. 中国矿业大学，江苏徐州221116；3. 河北师范大学化学与材料科学学院，石家庄 050000)摘要：采用熔体快淬结合去合金化法制备了钯锰纳米多孔材料(NP-PdMn)。

用X 射线衍射(XRD)、X 射线光电子能谱分析(XPS)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对材料进行了表征，并研究了其在碱性条件下对乙醇氧化的电催化活性。

表征显示，NP-PdMn 为具有三维双连续纳米多孔结构的棒状材料；锰取代了晶格中部分钯的位置使得晶面间距变小；部分钯和锰在材料表面以氧化态存在。

催化性能分析表明，与商业Pd/C 相比，NP-PdMn/C 催化剂具有优于商业Pd/C 的催化活性和稳定性。

关键词：金属材料；去合金化；钯锰纳米多孔材料(NP-PdMn)；电催化性能中图分类号：TM911.48 文献标识码：A 文章编号：1004-0676(2017)03-0020-08Electrocatalytic Oxidation of Ethanol by Palladium-Manganese Nanoporous MaterialCHEN Jiyun 1, 2, FANG Xiaoting 1, HAN Guangjie 1, 3, MEI Ling 1, 3, CUI Rongjing 1, HAN Zhida 1 *(1. Jiangsu Laboratory of Advanced Functional Materials, Changshu Institute of Technology, Changshu 215500, Jiangsu, China;2. China University of Mining and Technology, Xuzhou 221116, Jiangsu, China;3. College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050000, China)Abstract: Palladium-manganese nanoporous(NP-PdMn) material was prepared by the combination of melt spinning and dealloying techniques, and charaterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy analysis (XPS), scanning electron microscope(SEM) and transmission electron microscopy (TEM). The lectrocatalytic performance of the material for ethanol oxidation was tested under the alkaline conditions. The characterization results shows that NP-PdMn is a rod-like material with three-dimensional double continuous nanoporous structure. Manganese replaces the position of partial palladium in the lattice, making the crystal spacing smaller. Some Pd and Mn exist in oxidation state on the surface of the material. Compared with the commercial Pd/C, NP-PdMn/C catalyst has better catalytic activity and stability.Key words: metal materials; dealloying; PdMn nanoporous materials(NP-PdMn); electro-catalytic property燃料电池，尤其是低温燃料电池如质子交换膜燃料电池(PEMFC)、直接醇类燃料电池(DEFC)和碱性燃料电池作为清洁能源，受到越来越多的关注研究[1]。

其中直接醇类燃料电池存在电极动力学慢[2]、有机小分子等材料能量密度低、容易引起催化剂中毒等不足，其商业化生产仍面临挑战。

为降低燃料电池成本，提高催化效率，钯类催化剂的研究受到重视。

钯对小分子醇类有机物有较高的电催化活性，并且具有较高的化学稳定性[3-5]。

钯催化剂是近年来新兴的燃料电池催化剂，催化氧化效果显著[6-7]。

但钯作为催化剂应用在燃料电池中还存在一些问题，如钯在催化氧化过程中活性位很容易被中间产物占据，引起中毒而失去活性。

所以在催化剂制备过程中，人们考虑掺杂其他金属制成钯合金催化剂。

引入的金属可以提供较多的活性位或促进OH ads快速氧化占据活性位的中间物种，使催化剂的催化活性大为改善。

纳米多孔金属材料由于具有比表面积大、密度低及独特的物理、化学性能，在催化、传感等领域有广阔的应用前景。

制备多孔金属的方法主要有模板法，layer-layer自组装技术[8]及脱合金等。

模板法和Layer-layer自组装技术制备过程工艺复杂，成本高，杂质多，商业化应用受到限制。

脱合金又叫去合金化，是一种操作简单，高效且适用于大规模合成三维双连续纳米多孔材料的方法[9-17]。

Wang等[18]采用去合金化的方法，将PdAl合金中的铝选择性腐蚀去除，得到3~7 nm开放的双连续的纳米多孔的雷尼钯，电化学测量结果表明这种物质对于乙醇有较高的电催化活性和较好的稳定性。

Xu等[19-21]用去合金化法制备了多种纳米多孔(Nano-Porous，NP)材料NP-PdPt、NP-PdNi和NP-PdCu，并研究了其对甲酸、乙醇的催化以及氧还原性能测试，发现脱合金制备的样品有较高的电化学活性面积以及较好的稳定性。

有关脱合金过程中纳米多孔的形成过程，美国的Erlebacher课题组[22]建立了一个动力学模型，对Au-Ag合金脱合金化制备纳米多孔金过程中孔的形成和演化进行了研究。

发现去合金化的过程包括银的溶解和金的扩散，银溶解导致结构的粗化，金的扩散导致结构的平滑，它们之间的竞争导致了多孔结构的形成。

锰是地球中含量仅次于铁的过渡金属，自然界中+2、+3和+4价的锰最为常见。

根据热力学性质，Mn2+存在于缺氧和低pH值的环境中，Mn3+和Mn4+适于有氧和高pH值的环境[23-24]。

本文采用电弧熔炼和熔体快淬相结合的方法制备Pd15Mn5Al80合金条带，选择性腐蚀去除铝，得到钯锰纳米多孔材料(NP-PdMn)，研究了以炭载NP-PdMn修饰的电极对乙醇的电催化性能。

1实验1.1原料和试剂金属钯、锰、铝纯度(质量分数)均在99.9%以上，购自吉林东北有色金属有限公司。

商业Pd/C催化剂Pd/VX-72，美国Aldrich化学公司，钯质量分数为10%。

Nafion(5%溶液)，美国Sigma-Aldrich公司。

炭黑，美国Cabot公司。

无水乙醇为上海凌峰化学试剂有限公司，分析纯试剂。

实验用水为去离子水。

1.2钯锰纳米多孔材料(NP-PdMn)的制备将纯度(质量分数)在99.9%以上的钯、锰、铝金属，按Pd15Mn5Al80(质量分数)的配比配料，放入高真空电弧熔炼炉中，反复熔炼3次，得到Pd15Mn5Al80三元合金。

将合金用单锟旋淬仪甩成条带。

称取一定量的条带放入1 mol/L NaOH溶液中，在室温下自由腐蚀48 h。

将产物离心，用去离子水洗涤，置于真空干燥箱中烘干，得到黑色粉末状样品，即为钯锰纳米多孔材料NP-PdMn。

1.3NP-PdMn的表征采用X射线粉末衍射仪(日本Rigaku公司D/max-2200/PC型XRD)用于确定NP-PdMn的晶体结构；用扫描电子显微镜(德国ZEISS公司Sigma 型SEM)和配套能谱仪(EDS)观察粉末表面形貌和成分；用透射电子显微镜(美国FEI公司Tecnai G220S-TWIN型TEM)观察粉末微结构；用X射线光电子能谱(美国Thermo ESCALAB 250XI型XPS)分析NP-PdMn的电子结构。

1.4电化学测试1.4.1炭载催化剂制备用电子天平准确称量1 mg NP-PdMn、2 mg炭黑，加入离心管中；用移液枪向离心管中移入200 µL无水乙醇、20 µL Nafion(0.5%)和180 µL去离子水。

把试管放入超声波分散仪内超声混匀1 h。

制得PdMn/C含量为7.5 mg/mL的悬浊液。

对于电化学测试的数据结果质量归一化处理。

用同样的方法以Pd/VX-72商业催化剂制备相同含量Pd/C催化剂悬浊液。

1.4.2电极制备将玻碳电极在麓皮上用0.05 µm的Al2O3粉打磨干净后，用去离子水冲洗干净，超声30 s。

把电极放入铁氰化钾检测溶液中，用传统三电极体系扫描，当其循环伏安电势差在70 mV左右时，表明电极已打磨干净。

取出电极，用去离子水冲洗干净，自然晾干后即可使用。

测试前，将载体催化剂超声混匀10 min后，取4 µL悬浊液滴加在玻碳电极上，室温晾干后得到工作电极。

22 贵金属第38卷1.4.3电化学性能测试用电化学工作站(上海辰华仪器设备有限公司660型)对炭载催化剂电极进行电化学性能测试。

取1240 µL乙醇加入20 mL 1 mol/L KOH水溶液中，得到混合溶液。

测试前，所有电解液都通入高纯氮气20 min以去除溶液中的氧，测试过程均保持25℃，在氮气气氛下进行，扫描速率为50 mV/s。