揭示性气演变的NiMo合金中异常活动的起源
Yuefeng Zhang1,2, Wenqiang Yang3, Zhiyuan Zeng1
1Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong SAR, China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|December 27, 2025
概括
- (NiMo) 合金表现出极好的性演化反应 (HER) 活性. 氧重建的Ni3Mo(111) 表面显示出协同的Mo-Ni活性位点,推进了HER催化剂设计.
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:
- -合金 (NiMo) 合金因其在性进化反应 (HER) 中的高性能而闻名.
- 这些合金的精确活性相和反应机制在科学文献中仍是争论的主题.
- 了解这些方面对于优化催化剂设计和效率至关重要.
研究的目的:
- 解决围绕性HER过程中NiMo合金活性相和机制的模两可.
- 用先进的计算技术在现实的操作条件下建模催化剂行为.
- 为基于NiMo的HER催化剂建立一个最终的机制框架.
主要方法:
- 密度函数理论 (DFT) 的计算被用于模拟催化剂表面.
- 使用表面Pourbaix图表来模拟现实的操作条件.
- 开发了一种微动力学模型,以定量验证拟议的机制.
主要成果:
- 在运行条件下,催化剂表面通过氧气进行重建.
- 确定了一个协同机制,有 (Mo) 位点催化水解离, (Ni) 位点结合.
- 被O覆盖的Ni3Mo(111) 面由于水解离和吸附能量的低,表现出最佳性能.
- 预测的交换电流密度与实验值密切匹配,验证了微动力学模型.
结论:
- 该研究阐明了一种涉及氧重建NiMo表面的协同机制,用于性HER.
- 这些发现挑战了以前将氧化 (MoOx) 归因为主要活性部位的说法.
- 建立了一个强大的机械框架,为未来的HER催化剂提供合理的设计原则.
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