作为耐用和活性非白金组金属催化剂的潜在基础的十四个成员的宏循环复合结构
Zhiqing Feng1, Junya Ohyama2,3, Soutaro Honda1
1Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan.
Journal of the American Chemical Society
|April 25, 2025
概括
使用-复合体 (Co-14MR) 的新型非催化剂显示出增强的氧降解和演化反应. 热处理可以提高燃料电池和水分的性能和耐用性.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 开发非类金属 (非PGM) 催化剂对于高效的电化学反应至关重要.
- 在酸性条件下,质子交换膜燃料电池 (PEMFC) 和水分裂需要强大的催化剂来进行氧降解反应 (ORR) 和演化反应 (HER).
研究的目的:
- 开发和描述基于带有14个环形六宏环联体 (Co-14MR) 的-复合物的新型非PGM催化剂.
- 评估CO-14MR/C在酸性介质中的ORR和HER的催化活性和耐久性.
- 研究热处理对催化剂结构和性能的影响.
主要方法:
- 碳支持的 Co-14MR (Co-14MR/C) 催化剂的合成
- 对ORR和HER活性和耐久性的电化学测试.
- 在600°C时对Co-14MR/C进行热处理.
- 密度函数理论 (DFT) 计算以了解结构-活动关系.
- 结构分析 (例如,纽带长度,扭曲).
主要成果:
- 与传统的CoPc/ C相比,Co-14MR/ C的ORR和HER活性更高.
- Co-14MR/C的热处理显著提高了其催化性能.
- DFT计算显示热处理优化了中间吸附能量,改善了ORR和HER动力学.
- 与CoPc/ C和Fe-14MR/ C相比,Co-14MR/ C在ORR和HER中表现出更强的耐久性.
- 短 Co-N 债券和 CoN4 活性位点的最小扭曲有助于高耐久性.
结论:
- 碳-14MR结构代表了先进的非PGM电催化剂的有希望的设计.
- 热处理的CO-14MR/C为基催化剂和水分应用提供了可行的替代品.
- 了解影响催化活性和耐久性的结构因素是未来催化剂开发的关键.
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