The modification of oxide-derived Cu electrode with Ni, Zn, and Au was examined to improve the catalytic activity of COz electroreduction. The experimental results showed that Ni modification increased the Faraday efficiency of the formation of formic acid and n-propanol. The Faraday effi- ciency relating to the formation of the liquid products was as high as 34.3% at -1.5 V versus the saturated calomel electrode reference potential. In contrast, modification with Zn reduced the for- mic acid formation efficiency but enhanced the alcohol formation efficiency. Finally, modification with Au suppressed the selectivity toward the formation of both formic acid and alcohols.
以氧化铟锡(ITO)透明导电膜玻璃为基底,电化学恒电位法制备AuPd合金纳米粒子.系统考察了AuPd纳米粒子的组成和不同制备条件对其结构和电催化性能的影响.运用扫描电子显微镜(SEM)、X-射线能量散射谱(EDX)、X-射线衍射(XRD)、X-射线光电子能谱(XPS)和电化学方法进行表征.结果表明,制备的AuPd合金中Au:Pd元素比与投料比基本一致,纳米粒子分散均匀;AuPd合金纳米粒子对乙醇电氧化的催化活性和稳定性显著高于纯Pd纳米粒子.当沉积电位-0.3 V、Pd:Au=3:1时,Au1Pd3纳米粒子对乙醇电氧化表现出最高的催化活性和稳定性:其对乙醇氧化峰值电流密度是相同条件下制备的Pd纳米粒子的7.7倍,稳定测试1800 s时乙醇氧化的电流密度(1.05 mA cm^(-2))是Pd纳米粒子(0.02 mA cm^(-2))的52.5倍.