Roehrich Brian, Sepunaru Lior
Department of Chemistry and Biochemistry, University of California Santa Barbara, Building 232, Santa Barbara, CA, 93106, USA.
Angew Chem Int Ed Engl. 2020 Oct 19;59(43):19184-19192. doi: 10.1002/anie.202007148. Epub 2020 Aug 26.
While the electrochemical nanoimpact technique has recently emerged as a method of studying single entities, it is limited by requirement of a catalytically active particle impacting an inert electrode. We show that an active particle-active electrode can provide mechanistic insight into electrochemical reactions. When an individual Pt electrocatalyst adsorbs to the surface of a partially active electrode, further reduction of electrode-produced species can proceed on the nanocatalyst. Current transients obtained during hydrogen evolution allow simultaneous measurement of the Pt catalyst over different length scales, size dependency suggests H atom intercalation as a catalytic deactivation mechanism. Although results show that outer-sphere redox probes are unproductive for particle characterization, the breadth of inner-sphere electrochemical reactions makes this a promising method for understanding the properties of catalytic nanomaterials, one at a time.
虽然电化学纳米冲击技术最近已成为一种研究单个实体的方法，但它受到催化活性颗粒撞击惰性电极这一要求的限制。我们表明，活性颗粒-活性电极可以为电化学反应提供机理洞察。当单个铂电催化剂吸附到部分活性电极的表面时，电极产生的物种的进一步还原可以在纳米催化剂上进行。析氢过程中获得的电流瞬变允许在不同长度尺度上同时测量铂催化剂，尺寸依赖性表明氢原子嵌入是一种催化失活机制。虽然结果表明外层氧化还原探针对于颗粒表征没有效果，但内层电化学反应的广度使其成为一种一次理解一种催化纳米材料性质的有前途的方法。
