Carboxyl-Group-Bearing Metal Corroles of Cobalt, Manganese and Copper for Electrocatalytic Hydrogen Evolution.

5,15-bis(perfluorophenyl)-10-(4-carboxyphenyl) corrole and its Co(III), Mn(III), and Cu(III) corrole complexes were synthesized. The electrocatalytic hydrogen evolution reaction (HER) of these metal corrole complexes was investigated using different proton sources (AcOH, trifluoroacetic acid, and TsOH) in an organic dimethylformamide solvent. The electrocatalytic HER may proceed through EECC, EECEC, or EEECEC pathways (where E represents electron transfer and C represents proton binding) depending on the acidity and concentration of the proton source used. The Co corrole complex exhibits remarkable hydrogen production performance, achieving a turnover frequency of 201 s^-1 and a catalytic efficiency of 1.00. The examined metal corrole complexes also exhibit good HER activity in aqueous solution, with their catalytic activity following an order of 1-Co>1-Cu>1-Mn in both organic and aqueous phases.