通过具有Cis协调点的低旋铁复合体进行增强的氨氧化催化
Michael D Zott1, Jonas C Peters1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|May 17, 2021
概括
基于铁的催化剂对燃料电池中的氨氧化有希望. 一个新的铁复合物[bpyPy2Me) [MeCN) 2+在分子电催化中实现了149的创纪录的营业额.
科学领域:
- 电化学
- 催化剂
- 材料科学
背景情况:
- 氨 (NH3) 是一个关键的太阳能燃料候选物,在燃料电池中需要高效的氧化催化剂.
- 开发选择性和强大的电催化剂对于推进以氨为基础的能源技术至关重要.
- 铁 (Fe) 是地球上丰富的金属,使其成为催化应用中贵金属的有吸引力的替代品.
研究的目的:
- 为燃料电池应用开发高效的铁中介氨氧化 (AO) 电催化剂.
- 研究催化剂的结构和电子特性,以提高其性能和稳定性.
- 阐明由新型铁复合物介导的AO的催化机制.
主要方法:
- 铁复合物的合成和表征 [bpyPy2Me) Fe (MeCN) 2+ .
- 氨氧化催化剂的电化学评估,包括周转数 (TON) 和速率测量.
- 计算研究以探索反应途径和机械细节.
主要成果:
- [bpyPy2Me) 铁 (MeCN) 2+复合物实现了149个分子电催化器的创纪录的营业额 (),这比相关系统有很大的改进.
- 与之前报告的铁催化剂相比,该催化剂在较低的应用偏差 (~250 mV更低) 时显示出约50倍的AO速率.
- 电化学和理论数据表明一种涉及H原子抽象和随后的催化步骤的机制,确定了N-N键形成途径.
结论:
- 开发的铁复合物[bpyPy2Me) Fe2 MeCN2+代表了分子O2电催化学的重大进步.
- 连接体设计,特别是更强电场和更刚性的辅助连接体,增强了催化剂的稳定性和活性.
- 地球上丰富的铁是开发有效的氨氧化分子催化剂的可行金属,为可持续的能源解决方案铺平了道路.
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