Electrocatalysis of CO2 reduction by ruthenium benzothiazole and bithiazole complexes

Ru(2,2′-bipyridine)2[2-(2-pyridyl)benzothiazole]2+ is highly active for electrocatalytic reduction of CO2, while the 1-methylbenzimidazole analogue exhibits no activity. Comparison of the redox potentials for these two complexes suggests that reaction with CO2 may occur at the -S- of the benzothiazole ligand and this hypothesis is supported by results for Ru(2,2′-bipyridine)2(2,2′-bithiazole)2+ and Ru(2,2′-bithiazole)32+, which are both active for CO2 reduction.