Electrochemical Hydrogen Evolution by Cobalt (II) Porphyrins: Effects of Ligand Modification on Catalytic Activity, Efficiency and Overpotential
Electrochemical Hydrogen Evolution by Cobalt (II) Porphyrins: Effects of Ligand Modification on Catalytic Activity, Efficiency and Overpotential
复制标题
DOI：
10.1149/2.0481809jes
复制
发表时间：
2018-01-01
影响因子：
3.9
通讯作者：
Hung, Chen-Hsiung
中科院分区：
文献类型：
--
作者：
Beyene, Belete B.;Mane, Sandeep B.;Hung, Chen-Hsiung
以乙酸为质子源，在DMSO中研究了一系列在meso-苯环帕拉上具有吸电子（EW）和供电子（艾德）取代基的钴卟啉的电化学放氢行为.我们的研究表明，取代基的性质显着影响催化活性，效率和催化发生的潜力。通过调节卟啉取代基，法拉第效率（FE）从44%到99%，转换数（TON）从1.5到104（类似于11 h电解），转换频率（TOF）从0.23到9.1 h（-1），起始过电位从25到445 mV。与母体[Co（TPP）]相比，含-SO 3 H、-COOH或-NH 2取代基的钴卟啉具有更高的活性和效率，且起始电位更正.此外，以-COOMe、-OMe和-OH为取代基的配合物的低放氢活性也表明，meso-苯基取代基的酸性在催化过程中对提高放氢活性起着关键作用。作者（S）2018。由ECS发布。
Electrochemical H-2 evolution of a series of cobalt(II) porphyrins with electron-withdrawing (EW) and electron-donating (ED) substituents at the para positions of the meso-phenyl rings has been investigated in DMSO using acetic acid as a proton source. Our study showed that the nature of substituents significantly influences catalytic activity, efficiency, and the potential at which catalysis occurs. Faradaic efficiencies (FE) ranging from 44 to 99%, turnover numbers (TONs) from 1.5 to 104 (similar to 11 h electrolysis), turnover frequencies (TOFs) from 0.23 to 9.1 h(-1), and onset overpotentials from 25 to 445 mV were obtained by tuning the porphyrinic substituents. Cobalt porphyrins with -SO3H, -COOH, or -NH2 groups as the substituents showed high activity and efficiency with more positive onset potentials as compared to the parent [Co(TPP)]. Supports also from the low hydrogen generation activities for complexes with -COOMe, -OMe and -OH groups as the substituents suggest that the acidity of the meso-phenyl substituent plays a key role in enhancing the hydrogen evolution activities during the catalytic processes. (C)The Author(s) 2018. Published by ECS.