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采用化学还原法制备了碳纳米粒子支撑的钯纳米结构(Pd-CNP).透射电镜表征显示在Pd-CNP纳米复合物中,金属Pd呈菜花状结构,粒径约20~30 nm.它们由许多更小的Pd纳米粒子(3~8 nm)组成.电化学研究表明,Pd-CNP的电化学活性面积比商业Pd黑低40%,可能原因是部分Pd表面被一层碳纳米粒子覆盖,但其对甲酸氧化却表现出更好的电催化活性,质量比活性和面积比活性都比Pd黑高几倍.催化活性增强的原因可能是碳纳米粒子支撑的Pd纳米结构具有特殊的层次化结构,可以形成更多的活性位,以及表面位更利于反应进行.
The Pd-CNP supported on carbon nanoparticles was prepared by chemical reduction method. The transmission electron microscopy showed that the Pd was cauliflower in the Pd-CNP nanocomposite and the particle size was about 20-30 nm. Many smaller Pd nanoparticles (3 ~ 8 nm) .Electrochemical studies showed that Pd-CNP electrochemically active area is 40% lower than commercial Pd black, probably because part of the Pd surface is covered by a layer of carbon nanoparticles, But its oxidation for formic acid shows better electrocatalytic activity, and its specific activity and area specific activity are several times higher than that of Pd-black. The reason for the enhanced catalytic activity may be that the Pd nano-structure supported by carbon nano-particles has a special hierarchical structure The structure, which can form more active sites, and the surface sites more conducive to the reaction.