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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.
In this paper, about 120 nm of -Se sphere as a template, ascorbic acid as a reducing agent, H2PtCl6 as a precursor, by changing the amount of chloroplatinic acid can be synthesized with different shell thickness of nano Pt platinum balls (Pthollow) and its modified glassy carbon (Pthollow / GC). The structures of the samples were characterized by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), energy dispersive X-ray spectroscopy (XRD), X-ray diffraction (XRD) (SAED) pattern was used to characterize the morphology, composition and structure of the formic acid. The electrochemical oxidation of formic acid on Pthollow / GC electrode was investigated by cyclic voltammetry and chronoamperometry with formic acid as probe molecule. The prepared Pthollow has good dispersibility and relatively uniform particle size. The porous spherical shell is constructed by multi-dimensional and multi-level platinum atomic clusters and shows the structure and properties of polycrystalline platinum. When RPt / Se = 1.2, the synthesized Pthollow pair Formic acid has the highest electrocatalytic oxidation activity and is superior to Ptnano / GC electrode (Ptnano / GC), which provides some experimental and theoretical evidences for the optimized preparation of direct formic acid fuel cell (DFAFC) Potential application promotion value.