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以无定形硒溶胶为模板制备了不同硒覆盖度(θSe)(θSe=0.49,0.39,0.06,0)的Pt-Se和Pt纳米空球(分别记为(Pt-Se)HN和PtHN),发展了利用亚硫酸盐彻底除去核壳纳米粒子上Se的方法.对获得的纳米空球进行了形貌和结构的表征,结果表明所制备的(Pt-Se)HN粒径均匀,分散性好,球壳呈多孔结构.以其作为电催化剂制备了(Pt-Se)HN修饰的玻碳(GC)电极((Pt-Se)HN/GC),利用常规电化学方法比较该电极与PtHN/GC和商用碳载铂(Pt/C)修饰GC(Pt/C/GC)电极对甲酸的催化氧化作用,发现对甲酸氧化的活性顺序为(Pt-Se)HN/GC>PtHN/GC>Pt/C/GC.三种电极催化甲酸氧化的机理有所不同:前者更倾向于通过弱吸附中间体直接氧化成CO2的单途径机理进行,后两者则通过强吸附和弱吸附中间体的双途径机理进行.在一定Se覆盖度条件下,(Pt-Se)HN/GC对甲酸的氧化有助催化作用.
Pt-Se and Pt nanospheres with different selenium coverage (θSe) (θSe = 0.49,0.39,0.06,0) (Pt-Se HN and PtHN respectively) were prepared with amorphous selenium sol as templates. The method of completely removing the Se from the core-shell nanoparticles by sulphite was developed.The morphologies and structures of the obtained nanospheres were characterized.The results show that the prepared Pt-Se HN particles are uniform in size and dispersive (Pt-Se) HN-modified GC electrode (Pt-Se) HN / GC was prepared by using it as an electrocatalyst.The electrode was compared with PtHN / The catalytic oxidation of formic acid by GC and Pt / C modified GC (Pt / C / GC) electrodes showed that the order of the activity for formic acid oxidation was (Pt-Se) HN / GC> PtHN / GC> Pt / C / GC. The mechanism of the catalytic oxidation of formic acid by the three kinds of electrodes is different: the former is more likely to proceed through the single pathway mechanism of direct oxidation of weakly adsorbed intermediates to CO2, and the latter two pass through the double (Pt-Se) HN / GC promoted the oxidation of formic acid under a certain Se coverage.