对碳催化剂激活的内在机械影响
Bowen Liu1,2, Shuaishuai Xu1, Yang Gao1
1CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST), Beijing 100190, China.
Journal of the American Chemical Society
|January 23, 2025
概括
机械应变可显著增强碳基无金属催化剂 (C-MFCs) 的氧降解反应 (ORR). 通过优化中间吸附,对有缺陷的石墨碳施加拉伸应变,从而为机电催化开辟了道路.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 基于碳的无金属催化剂 (C-MFC) 是高贵金属催化剂的有希望的替代品.
- 由于其他结构因素的复杂性,机械应变对C-MFC的影响仍未得到充分研究.
- 了解应变效应对于推进C-MFC应用至关重要.
研究的目的:
- 研究压力对石墨碳催化剂的机械效应.
- 确定氧降解反应 (ORR) 的表面应变与催化活性之间的相关性.
- 阐明应变对C-MFCs的影响的基本原则.
主要方法:
- 开发一个用于对高度定向的溶解石墨 (HOPG) 进行连续应变的平台.
- 在施加拉伸应变下同时收集电化学信号.
- 密度功能理论 (DFT) 模拟以了解应变诱导的缺陷修饰.
主要成果:
- 拉力压力没有激活HOPG中原始的内平面或边缘碳部位.
- 在存在内平面缺陷的情况下,ORR催化活性显著且可重复增强.
- 在有缺陷的HOPG上,ORR电流密度得到了∼35.0%的改善.
- DFT模拟确定了Ston-Wales缺陷作为压力介导的中间吸附优化的关键位置.
结论:
- 表面应变可以显著调节ORR缺陷石墨碳的催化活性.
- 缺陷的应变工程为开发高性能C-MFC提供了一条新途径.
- 这项研究为新兴的碳基机电催化领域奠定了基础.
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