Acridinium salts as metal-free electrocatalyst for hydrogen evolution reaction

Here we report the purely organic metal-free electrocatalyst — acridinium salt 9-phenyl-10-methylacridinium iodide for hydrogen evolution reaction. A controlled potential electrolysis experiment in present 9-phenyl-10-methylacridinium iodide with a simultaneous gas chromatographic analysis confirmed the catalytic production of molecular hydrogen. The behavior of the catalytic wave is typical for a “total catalysis”. A mechanism involving initial reduction of PhAcr⁺/PhAcr and subsequent protonation is proposed.