Methylthiophenyl- and Methylthiobiphenyl-Substituted A 2 B Co III corroles: Modulating Electrocatalyzed Hydrogen Evolution Reactions on Surface-Modified Gold Electrodes

Four A B-type Co corroles ( ) with electron-donating/withdrawing substituents at the A -aryl substituents and a 4-(methylthio)phenyl ring at the B position have been synthesized and characterized, along with a series of -extended Co corroles ( - ) with 4'-(methylthio)biphenyl moieties. The electronic structures and structure-property relationships of the dyes have been analyzed by comparing their redox and optical properties to trends predicted in density functional theory calculations. Au electrodes surface-modified with - and - are highly efficient catalysts for electrocatalyzed hydrogen evolution reactions, and the electrocatalytic properties can be readily modulated by fine-tuning the electronic structure of the Co corrole and the distance between the "Au-S" bond and Co center.