Electrocatalytic Hydrogen Evolution Reaction Using meso- tetrakis-(pentafluorophenyl)porphyrin iron(III) chloride

Abstract

This study focuses on the electrochemical catalysis of proton reduction into hydrogen using meso- tetrakis-(pentafluorophenyl)porphyrin iron(III) chloride in the presence of Et3NHCl. Indeed, the direct reduction of Et3NHCl on vitreous carbon electrode occurs at Ep -1.6 V vs Ag/AgCl in [Bu4N][BF4]-CH3CN, whereas the reduction potential shifts to -1.3 V vs Ag/AgCl in the presence of Fe(PFTPP)Cl. Based on the gas chromatography analysis, the formation of H2, with a current efficiency of ca. 58% after 3.8 h, is achieved with a yield of 8 μmoles and a turnover number of 8 while the chemical yield was about 80%. These results reflect the effect of the presence of electron withdrawing pentafluorophenyl groups around the metal in Fe(PFTPP)Cl.