Helmholtz Young Investigator Group Nanoscale Operando CO2 Photo-Electrocatalysis, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin, Germany.
Department of Interface Science, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany.
J Am Chem Soc. 2023 Mar 8;145(9):5242-5251. doi: 10.1021/jacs.2c12617. Epub 2023 Feb 22.
Rational innovation of electrocatalysts requires detailed knowledge of spatial property variations across the solid-electrolyte interface. We introduce correlative atomic force microscopy (AFM) to simultaneously probe, and at the nanoscale, electrical conductivity, chemical-frictional, and morphological properties of a bimetallic copper-gold system for CO electroreduction. In air, water, and bicarbonate electrolyte, current-voltage curves reveal resistive CuO islands in line with local current contrasts, while frictional imaging indicates qualitative variations in the hydration layer molecular ordering upon change from water to electrolyte. Nanoscale current contrast on polycrystalline Au shows resistive grain boundaries and electrocatalytically passive adlayer regions. conductive AFM imaging in water shows mesoscale regions of low current and reveals that reduced interfacial electric currents are accompanied by increased friction forces, thus indicating variations in the interfacial molecular ordering affected by the electrolyte composition and ionic species. These findings provide insights into how local electrochemical environments and adsorbed species affect interfacial charge transfer processes and support building structure-property relationships in catalysis and energy conversion research.
理性创新的电催化剂需要详细了解固体电解质界面的空间特性变化。我们引入相关原子力显微镜（AFM）来同时探测和纳米尺度下的双金属铜金系统的电导率、化学摩擦和形态特性，用于 CO 电还原。在空气、水和碳酸氢盐电解质中，电流-电压曲线显示出与局部电流对比相对应的电阻性 CuO 岛，而摩擦成像表明，在从水到电解质的变化过程中，水化层分子有序性发生了定性变化。多晶 Au 上的纳米级电流对比显示出电阻性晶界和电催化惰性吸附层区域。在水中进行的导电 AFM 成像显示出低电流的介观区域，并表明界面电流的降低伴随着摩擦力的增加，这表明界面分子有序性受到电解质组成和离子种类的影响而发生变化。这些发现深入了解了局部电化学环境和吸附物种如何影响界面电荷转移过程，并支持在催化和能量转换研究中构建结构-性能关系。
