在电化学沉积铂纳米粒子的过程中,通过添加卤素阴离子,可以显著地改变纳米粒子的形貌.通过添加氯离子、溴离子和碘离子,可以在导电基底上分别获得球形、片状及立方结构的铂纳米粒子.对卤素阴离子影响电沉积铂纳米粒子形貌的原因进行了探讨.研究了铂纳米粒子的电催化活性,发现通过添加卤素阴离子制备得到的铂纳米粒子对于甲醇的电化学催化氧化表现出较低的电化学催化活性.通过电化学氧化法全部或部分除去铂表面吸附的卤素阴离子后,纳米粒子对甲醇的电化学催化氧化活性显著提高.%The morphology of Pt nanoparticles can be well controlled by introduction of halide ions during electrochemical deposition of platinum. Spherical, flake and cubic Pt nanoparticles were obtained on conductive substrates by the addition of chloride, bromide and iodide into electrodeposition system, respectively. The origin of the halide-dependent morphology of Pt nanoparticles was discussed. The electrocata-lytic properties of Pt nanoparticles were investigated and it was found that the introduction of halide ions significantly lowers the catalytic activity of Pt nanoparticles toward methanol electrooxidation. The catalytic activity of Pt nanoparticles can be greatly improved by an electrochemical oxidation procedure in which the adsorbed halide ions can be partially or totally removed from the surface of Pt nanoparticles.
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