纳米Pd上H_2O_2的电催化还原反应

Electrocatalytic Reduction of Hydrogen Peroxide on Pd Nanoparticles

利用纳米Pd颗粒修饰的Au旋转圆盘电极,通过强制对流条件下的线性电势扫描伏安法,研究了酸性介质中H2O2在纳米Pd催化剂上的电还原反应.动力学研究结果表明,H2O2在纳米Pd上电还原反应的表观活化能为27.6kJ·mol-1,反应为2电子转移过程,电解质的阴离子类型显著影响纳米Pd对H2O2电化学还原反应的催化性能.根据动力学电流与H2O2浓度及与H+浓度的关系,提出了Pd催化H2O2电还原反应可能的速率控制步骤,并讨论了其可能的反应机理.

Electrocatalytic reduction of H2O2 on Pd nanoparticles in acidic medium was investigated by linear potential sweep method using an Au rotating disk electrode covered with Pd nanoparticles. The apparent activation energy for electroreduction of H2O2 on Pd nanoparticles was determined to be around 27.6 kJ·mol^-1. The reaction proceeds via a two electron process. The type of anion of electrolytes significantly affected the catalytic behavior of Pd nanoparticles. A possible rate-determining step was proposed based on the dependence of kinetic current on the concentration of H2O2 and proton. The reaction mechanism was briefly discussed.