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易斯酸介导界面供水,用于可持续的质子交换膜水电解
Liming Deng1, Hongjun Chen1, Sung-Fu Hung2
1College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Journal of the American Chemical Society
|December 11, 2024
概括
研究人员使用易斯酸开发了一种用于水电解的新催化剂策略,以改进RuO2催化剂
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 催化剂-电解质接口对于质子交换膜水电解 (PEMWE) 是至关重要的.
- 在PEMWE中优化界面结以提高催化活性和稳定性是一项挑战.
- 二氧化鲁 (RuO2) 是氧化演化反应 (OER) 的关键催化剂,但面临稳定性问题.
研究的目的:
- 提出一种新的催化剂设计策略,以提高PEMWE中的RuO2的性能和稳定性.
- 调查硬的易斯酸在催化剂表面调解界面结和水管理中的作用.
- 展示一种改善基于Ru的催化剂耐用性的新方法.
主要方法:
- 在催化剂设计中应用硬软酸原理.
- 与RuO2结合硬的易斯酸 (LAs),如ZrO2,TiO2和HfO2.
- 使用先进技术对水界动态和质子转移进行机械分析.
- 在酸性OER和PEMWE条件下对催化剂性能和长期稳定性的电化学测试.
主要成果:
- 易斯酸重新配置了界面结,增强了RuO2催化站点的水捕获和反应剂供应.
- 一个相互连接的结网促进了快速的质子转移,减少了表面的酸性,并防止了催化剂的腐蚀.
- ZrO2-RuO2的OER超电位显著降低,达到170mV.
- 优化的催化剂表现出高耐用性,在酸性OER下维持1800小时,在PEMWE下维持100小时的2A cm-2.
结论:
- 拟议的硬软酸策略有效地提高了PEMWE的RuO2催化剂的活性和稳定性.
- 易斯酸介导的界面水管理为克服传统Ru基催化剂的局限性提供了有希望的途径.
- 这种方法在开发水分技术的强大的电催化剂方面具有广泛的适用性.
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