激活的单位金属催化剂打破了吸附-能量缩放关系,从而实现了强大的双功能氧催化剂
Zhongke Yuan1,2,3, Jing Li1,2,3, Zhengsong Fang1
1Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou, China.
Angewandte Chemie (International ed. in English)
|May 28, 2025
概括
研究人员开发了一种新的金属-碳-催化剂,可以克服氧气演变和还原反应 (OER/ORR) 的局限性,显著提高可再生能源技术性能.
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
- 可再生能源可再生能源是可再生能源.
背景情况:
- 电催化氧演变和还原反应 (OER/ORR) 对可再生能源至关重要.
- 贵金属催化剂占据主导地位,但面临着活动和耐用性挑战.
- 原子分散过渡金属催化剂提供了替代品,但需要提高性能.
研究的目的:
- 设计一个超越OER/ORR通用吸附能量扩展限制的单金属位点催化剂.
- 为了提高过渡金属催化剂的双功能催化性能.
- 为能源应用开发具有卓越活性和耐久性的催化剂.
主要方法:
- 开发了一种新的金属-碳- (金属-C-B) 催化剂结构.
- 利用金属碳协调和兴奋剂用于催化剂稳定和电子调.
- 对OER/ORR的性介质和可充电Zn-空气电池的催化剂性能进行了研究.
主要成果:
- 优化的Co-C-B催化剂实现了创纪录的低OER超电位 (172mV) 和高ORR半波电位 (0.87V).
- 在连续的OER/ORR和Zn空气电池中超过6755个循环中,经过500小时的强大稳定性.
- 实现了比商业贵金属催化剂显著更高的质量活动 (∼112/80倍).
结论:
- 金属-C-B催化剂的设计打破了对双功能OER/ORR的吸附能量的缩放限制.
- 原子分散的CoC4Bx部分作为独特的活性中心,增强了超出理论限制的催化活性.
- 这一突破为可再生能源技术中先进的催化剂提供了有希望的途径.
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