在高的MXenes中发生进化反应:对原子配置的洞察
M H Ghoncheh1, Z W Chen1, P G Demingos1
1Department of Materials Science and Engineering, University of Toronto, 184 College Street, Toronto, ON M5S 3E4, Canada.
iScience
|October 23, 2025
概括
高的MXenes表现出进化反应 (HER) 的增强催化活性. 这些材料中的组合调和原子排序为扩散创造了高效的途径,并降低了能源障碍.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 计算化学的计算化学
背景情况:
- 高性 (HE) MXenes由于多样化的活性位点和可调节的组成,提供了增强的催化活性和稳定性.
- 在合成过程中溶液分离可能导致偏好的原子分布,对催化性能产生负面影响.
研究的目的:
- 为了评估M2C(-T) 2MXenes的HE变体,对于演化反应 (HER) 有不同的表面终点.
- 研究组合调和原子排序对HER性能和稳定性的影响.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 水晶轨道汉密尔顿人口 (COHP) 分析.
- 评估吸附和扩散能量.
主要成果:
- 用其他过渡金属替代Ti,改善了H*的吸附和扩散.
- (Mo) 原子表现出具有强大的Mo-Mo相互作用的短距离排序,促进H*扩散通路.
- 气溢出显著降低了HER的Volmer-Tafel屏障,从0.94 eV降至0.48 eV.
- OH终端的HE MXenes表现出良好的热力学和机械稳定性 (Young的模量~170 N/m,剪切模量~68 N/m).
结论:
- 设计HE MXenes的组成可以诱导有利的短距离原子排序.
- 这种排序通过创建多个扩散路径来促进进化反应 (HER).
- HE MXenes,特别是 OH 终结的变体,显示出作为 HER 的稳定和高效的电催化剂的希望.
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