Pt纳米空球壳厚的可控制备及对甲酸的电催化氧化  

Platinum hollow nanospheres with different shell thickness:Controllable synthesis and electrocatalyst for the oxidation of formic acid

作　　者：林剑云[1] 程美琴[1] 张贤土[1] 商中瑾 熊婷[1] 林旋[1] 田伟[1] 钟起玲[1] 任斌[2,3] 

机构地区：[1]江西师范大学化学化工学院化学系,南昌330022 [2]固体表面物理化学国家重点实验室 [3]厦门大学化学化工学院,厦门361005

出　　处：《中国科学：化学》2013年第11期1520-1526,共7页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(20663002);厦门大学固体表面物理化学国家重点实验室基金(200511);江西省自然科学基金(0620025)资助

摘　　要：本文以约120 nm的-Se球为模板,抗坏血酸为还原剂,H2PtCl6为前驱体,通过改变氯铂酸的用量可控合成了不同壳厚的纳米铂空球(Pthollow)及其修饰玻碳(GC)电极(Pthollow/GC);采用扫描电子显微镜(SEM)、高分辨透射电子显微镜(HR-TEM)、能量色散X射线(EDX)谱、X射线衍射(X-ray diffraction,XRD)谱和选区电子衍射(SAED)图等表征其形貌、组成与结构;以甲酸为探针分子,采用循环伏安和计时电流法研究了甲酸在Pthollow/GC电极上的电催化氧化行为.结果表明,所制备的Pthollow分散性好、粒径比较均匀,其多孔球壳是由多维多级的铂原子团簇所构建,呈现多晶铂的结构与性质;当RPt/Se=1.2时,所合成Pthollow对甲酸的电催化氧化活性最高,且明显优于电沉积铂(Ptnano)修饰GC电极(Ptnano/GC),为直接甲酸燃料电池(DFAFC)阳极材料的优化制备提供了一定的实验与理论依据,有潜在的应用推广价值.Pt hollow nanospheres with different shell thicknesses were synthesized by adjusting the amount of precursor H2PtC16, using 120 nm of a-selenium colloids as the template, ascorbic acid as the reducing agent, and SDSN as stabilizing agent. The prepared platinum hollow spheres were drop-coated to modify the glassy carbon electrode （Pthollow/GC） and used as the working electrode. Scanning electron microscope （SEM）, high resolution transmission electron microscope （HR-TEM）, energy dispersive X-ray spectrum （EDX）, X-ray diffraction （XRD） and selected area electron diffraction （SAED） were used to determine the morphology and structure. The electrocatalytic oxidation behavior of formic acid on the modified electrodes was evaluated by cyclic voltammetry and chronoamperometry. The results show that the Pt hollow nanospheres have a uniform particle size and good dispersity. The shell of the spheres were made of Pt clusters of various size, showing the similar structure and propertie to that of the polycrystalline platinum. Hollow nanospheres showed different electrocatalytic activity on the oxidation formic acid at a different molar ratio between Se and Pt. The Pt hollow nanosphere with a molar ratio of 1：1.2 shows the highest activity, and is much more active than the electrodeposited Pt on glassy carbon surface. These provides theoretical and experimental conditions for the anode material of direct formic fuel cell, and has potential value of application.

关 键 词：铂纳米空球 可控制备 甲酸 电催化氧化 

分 类 号：O643.32[理学—物理化学] TB383.1[理学—化学]