Department of Chemistry, Stanford University, Stanford, CA, USA.
Department of Chemistry, University of Warwick, Coventry, UK.
Nat Mater. 2021 Jul;20(7):1000-1006. doi: 10.1038/s41563-021-00958-9. Epub 2021 Mar 18.
Understanding how the bulk structure of a material affects catalysis on its surface is critical to the development of actionable catalyst design principles. Bulk defects have been shown to affect electrocatalytic materials that are important for energy conversion systems, but the structural origins of these effects have not been fully elucidated. Here we use a combination of high-resolution scanning electrochemical cell microscopy and electron backscatter diffraction to visualize the potential-dependent electrocatalytic carbon dioxide [Formula: see text] electroreduction and hydrogen [Formula: see text] evolution activity on Au electrodes and probe the effects of bulk defects. Comparing colocated activity maps and videos to the underlying microstructure and lattice deformation supports a model in which CO electroreduction is selectively enhanced by surface-terminating dislocations, which can accumulate at grain boundaries and slip bands. Our results suggest that the deliberate introduction of dislocations into materials is a promising strategy for improving catalytic properties.
了解材料的体相结构如何影响其表面的催化作用，对于开发可行的催化剂设计原则至关重要。体相缺陷已被证明会影响对能源转换系统很重要的电催化材料，但这些影响的结构起源尚未完全阐明。在这里，我们使用高分辨率扫描电化学池显微镜和电子背散射衍射相结合的方法，可视化金电极上电催化二氧化碳[公式：见文本]还原和析氢[公式：见文本]活性的电位依赖性，并探测体相缺陷的影响。将共定位的活性图谱和视频与底层微结构和晶格变形进行比较，支持了这样一种模型，即表面终止位错选择性地增强 CO 电还原，位错可以在晶界和滑移带处累积。我们的结果表明，有目的地在材料中引入位错是提高催化性能的一种很有前途的策略。
