Pd-Cu/C上甲酸根电催化氧化及其去合金化效应

Abstract

以柠檬酸钠为稳定剂，通过一锅法在乙二醇体系中制得高分散的Pd-Cu/C二元合金催化剂. 用高分辨透射电镜和XRD观察、表征其形貌和结构，经重复循环扫描对Pd-Cu/C催化剂进行去合金化处理，研究了去合金效应对甲酸根电催化氧化性能的影响. 通过吸附CO的原位ATR-IR光谱测量，初步探讨了去合金前后催化剂表面结构的改变. 研究表明，Cu的去合金化可提高Pd-Cu/C电极初始的电催化氧化活性，但不利于其长时间的活性保持；合金化Pd-Cu/C电极电催化稳定性有显著的优势.

Carbon supported highly dispersed Pd-Cu nanoalloy catalyst toward formate electrooxidation is prepared via one-pot synthesis by using ethylene glycol as the reducing agent and sodium citrate as the stabilizer. The as-prepared catalyst is structurally characterized by TEM and XRD. The Cu dealloyment is carried out through repetitive potential cycling of the Pd-Cu/C catalyst in an acidic solution. The dealloying effect on the performance of the Pd-Cu/C is investigated by using cyclic voltammetry and chronoamperometry, and the surface structural change of Pd-Cu/C is probed by in situ ATR-IR measurement. The results show that the as-prepared Pd-Cu/C processes a better long-term stability than the dealloyed one in electrocatalytic oxidation of formate, while the dealloyed Pd-Cu/C exhibits a higher initial electrocatalytic activity.