Photoelectrocatalytic CO2 reduction based on metalloporphyrin-modified TiO2 photocathode

Abstract The conversion of CO 2 and water to value-added chemicals under sunlight irradiation, especially by photoelectrocatalytic reduction process, is always a dream for human beings. A new artificial photosynthesis system composed of a metalloporphyrin-functionalized TiO 2 photocathode and BiVO 4 photoanode can efficiently transform CO 2 and water to methanol, which is accompanied by oxygen release. This photoelectrocatalytic system smoothly produces methanol at a rate of 55.5 µM h −1 cm − 2 , with 0.6 V being the membrane voltage in plants. The production of hydrogen can also be observed when the voltage is more than 0.75 V, due to photocatalysis. Our results evidently indicate that the molecules of metalloporphyrin attached onto the surface of anatase (TiO 2 ) behave as chlorophyll, NADP, and Calvin cycle in plant cells.