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在色酸盐催化剂中的电子吸收效应促进在中性水溶液中均质的光催化进化

Chengyu Liu¹, Titus de Haas¹, Francesco Buda¹

¹Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, P.O. Box 9502, 2333CC Leiden, The Netherlands.

ACS catalysis

|March 27, 2025

概括

电子贫乏分子催化剂在中性pH下在演化反应 (HER) 中表现出惊人的活性,其性能优于电子丰富的催化剂. 这项研究揭示了电子调在光催化条件下如何影响HER机制.

科学领域:

催化剂是一种催化剂.
摄影化学的使用.
材料科学材料科学材料科学

背景情况:

分子催化剂为机械学研究提供可调节的电子特性.
进化反应 (HER) 对可持续能源至关重要.
了解替代剂对催化剂活性的影响是优化HER的关键.

研究的目的:

调查电子捐赠和电子取消替代剂对HER的和色胺催化剂的影响.
在不同的pH条件下阐明光催化HER的机械路径.
为了比较富含电子的催化剂与缺乏电子的催化剂的性能.

主要方法:

阳离子M=Co(III) - 和M=Zn(II) - 氨酸复合物的合成和表征.
使用[Ru(bpy) ]2+光敏感剂和蓝光照射的均质光催化HER实验.
密度函数理论 (DFT) 计算以探测反应机制.

主要成果:

富含电子的[Co(OMeP) ]3-在酸性介质中表现出更高的活性 (pH 4.1).
在中性介质中表现出更大的活性 (pH 7.0).
机制因pH而有所不同:在酸中减少Co (III) -H的质子合,在中性条件下减少以接体为基础.

结论:

替代电子效应显著控制了她的活动和机制.
电子贫穷的催化剂可以在中性pH附近的电子丰富的催化剂中表现出色.
这项工作为设计HER的高效分子催化剂提供了洞察力.

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