构建梯度轨道合以诱导Pt-碳化物电催化剂中的反应性金属支相互作用以实现有效的甲醇氧化
Shenzhou Li1, Gang Wang2, Houfu Lv3,4
1State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Journal of the American Chemical Society
|June 21, 2024
概括
一种新的策略在化碳催化剂中诱导了反应性金属支相互作用,从而产生了新的金属间电催化剂. 通过减弱CO吸附,L12-Pt3Ti-TiC催化剂显示出优异的甲醇氧化活性.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 反应性金属支相互作用 (RMSI) 是调整支金属催化剂性能的一个关键策略.
- 通过热还原常规的RMSI诱导通常会导致金属封装,阻碍机械研究和应用.
- 需要采用无减少剂的方法来克服RMSI研究和应用的局限性.
研究的目的:
- 在不使用减光剂的情况下,开发一种在碳化物系统中诱导RMSI的新方法.
- 合成和描述L12-Pt3M-MCx金属间电催化剂.
- 研究RMSI诱导的机制及其对催化活性的影响,特别是甲醇氧化.
主要方法:
- 使用梯度轨道合构建策略来诱导RMSI.
- 用密度功能理论 (DFT) 的计算来阐明电子结构和反应机制.
- 使用半细胞测试和直接甲醇燃料电池评估了电化学性能.
主要成果:
- 该策略成功诱导了Pt碳化物系统中的RMSI,形成了L12-Pt3M-MCx金属间电催化剂 (M = Ti,Zr,Hf,V,Nb,Ta,Cr,Mo,W).
- DFT计算显示,梯度d(M) - 2p ((C) - 5d ((Pt) 轨道合促进了电子转移,C空位形成和M迁移,推动了RMSI.
- L12-Pt3Ti-TiC催化剂在酸性甲醇氧化反应 (MOR) 中表现出极高的活性,其质量活性为2.36 A mgPt-1和峰值功率密度为187.9 mW mgPt-1.
- DFT分析表明L12- Pt3Ti- TiC通过将吸附点从Pt转移到Ti来减弱*CO吸附,从而提高MOR性能.
结论:
- 无减少剂的策略通过梯度轨道合和空隙形成有效地诱导Pt碳化物系统中的RMSI.
- 由此产生的L12-Pt3Ti-TiC金属间电催化剂在甲醇氧化方面表现出最先进的性能.
- 这些发现为RMSI机制提供了基本的见解,并为设计先进的电催化剂提供了有希望的途径.
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