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氧化金属-合物合作性使得在中性pH下具有宏循环铜复合物的水氧化催化剂具有稳定性和有效性
Pablo Garrido-Barros1, Dooshaye Moonshiram2, Marcos Gil-Sepulcre1
1Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology (BIST), Avinguda Països Catalans, 16, 43007 Tarragona, Spain.
Journal of the American Chemical Society
|September 16, 2020
概括
一种新型的铜复合物具有高度非局部化的四胺酸宏循环连接体 (TAML),表现出优异的水氧化催化. 这种先进的催化剂在中性pH下实现了高效率和稳定性,优于具有较少脱局的配体的相关系统.
科学领域:
- 无机化学
- 催化剂
- 人工光合作用
背景情况:
- 水氧化催化对于人工光合作用设备至关重要.
- 晚期第一排过渡金属复合物提供廉价的催化剂平台.
- 挑战包括获得高氧化状态和金属-连接体可变性.
研究的目的:
- 作为水氧化催化剂,探索一个具有扩展π-移位的四氨基酸宏循环连接体 (TAML) 的铜复合体.
- 将其活动和稳定性与具有较低π移位的类似系统进行比较.
- 研究金属-连接体合作性和电荷转移在催化性能中的作用.
主要方法:
- 铜复合物的合成和表征,具有不同的联体π-移位.
- 在中性pH条件下评估水氧化催化活性.
- 分析催化降解途径和稳定机制.
主要成果:
- 具有扩展TAML连接体 (1^2-) 的铜复合体表现出增强的金属连接体合作性以容纳氧化等价物.
- 在1^2-中有效的电荷移位稳定了氧化电荷,从而显著提高了催化性能 (k_obs = 140 s^-1在200 mV的超电位).
- 具有较低π-移位 (2^2-) 的类似复合物降解,而非循环复合物 (3^2-) 在中性pH下是不稳定的.
结论:
- 在TAML联体中扩展的π-移位对于稳定氧化电荷和实现高水氧化催化活性至关重要.
- 通过电荷转移促进的金属-合物合作性是基于TAML的铜复合物的卓越性能和强度的关键.
- 在中性pH下,宏循环稳定对于催化剂的寿命和性能至关重要.
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