Abstract
Electrochemical hydrogenation of chlorodifluoromethane (HCFC-22) was attempted using metal- and metal–phthalocyanine (PC)-supported gas diffusion electrodes (GDEs). Among these modified GDEs, only the Co–PC-supported GDE showed electrocatalytic activity for HCFC-22 hydrogenation, with decomposition to methane and difluoromethane (HFC-32). The efficiency for hydrogenation and HFC-32 selectivity increased with negative increase in the potential during electrolysis. This potential dependence of hydrogenation efficiency suggests that electrons are transferred to HCFC-22 not from the Co(I) metal center, but from the reduced PC ring, and that the Co(I) metal center acts as the adsorption site for HCFC-22.