Metal-Free Xanthene-Bridged Bis-Corrole: Synthesis and Efficient Electrocatalytic Hydrogen Evolution

A new metal-free xanthene-bridged bis-corrole had been synthesized and used as a catalyst for electrocatalytic hydrogen evolution reaction for the first time. This bis-corrole demonstrated high catalytic efficiency in DMF and acetonitrile-aqueous solution upon using acetic acid as the protons source. The turnover frequency (TOF) could reach 627.75 h–1 in DMF at the overpotential of 924 mV and 581.42 h–1 in neutral buffer acetonitrile-aqueous solution at the overpotential of 828 mV. The prepared bis-corrole also exhibted good stability in the electrolysis. This study highlights that linking one corrole macrocycle to another can lead to the metal-free bis-corrole as a stable HER catalyst.