表面终结 (-O, -F或 -OH) 和金属兴奋剂对Mo2CTxMXene的HER活动的影响
Huidong Li1, Yuping Chen1, Qing Tang1
1School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Chemical Theory and Mechanism, Chongqing University, Chongqing, 401331, China.
概括
在Mo2CTx MXenes中,混合功能化和过渡金属兴奋剂显著增强演化反应 (HER) 活性. 这项研究指导了用于高效能源应用的先进MXene电催化剂的开发.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 计算化学计算化学
背景情况:
- 二维MXenes是进化反应 (HER) 的有希望的电催化剂.
- 以前的研究往往忽略了混合功能组对MXene HER性能的影响.
- 实验MXenes通常表现出混合的表面终端.
研究的目的:
- 研究混合功能化Mo2CTx MXenes的HER特性.
- 评估同时存在的O,F和OH功能群对催化活性的影响.
- 探索过渡金属兴奋剂以进一步提高她的表现.
主要方法:
- 混合功能化Mo2CTx MXenes (T=-O, -F, -OH) 的理论研究.
- 对HER中间体的电子结构和吸附能量的分析.
- 过渡金属 (Fe,Co,Ni,Cu) 兴奋剂效应的计算选.
主要成果:
- 通过调节H吸附,二进制O/F共功能化改善了HER活动,而不是O终端的Mo2CO2.
- 三级O/F/OH功能表现出有限的HER增强,原因是H吸附能力较弱.
- 过渡金属兴奋剂减少了对氧的电荷转移,增强了H吸附和整体HER活性.
结论:
- 混合功能化和过渡金属兴奋剂为Mo2CTx MXenes中的高HER性能提供协同效应.
- 这项研究为设计先进的MXene电催化剂提供了一个框架.
- 这些发现适用于优化其他MXene电催化系统中的HER活性.
相关概念视频
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