Mesoporous TS-1 zeolite-confined metal oxides photocathode for efficient reduction of carbon dioxide to methanol

Abstract

Excessive CO2 emission has caused serious environmental problems, and converting CO2 to high value-added fuels is attractive for solving energy and environmental crisis. Herein, a novel mesoporous TS-1(mTS-1) zeolite-confined metal oxides nanoclusters Cu-Bi@mTS-1 was developed for efficient photoelectrochemical reduction reaction of CO2 (PEC CO2RR). The catalyst Cu-Bi@mTS-1 as a photocathode showed high activity, achieving a maximum methanol Faraday efficiency (FECH3OH) of 93.4 % at −0.7 V vs. RHE. The C2 product ethanol could be also detected at higher potentials during PEC CO2RR. In-situ FTIR results indicate the occurrence of key reaction intermediates *CO, *CHO, *OCCO and *COCHO during the conversion of CO2 to CH3OH and CH3CH2OH. It is believed that the hierarchically porous structure of mTS-1 is conducive to the enrichment of CO2 molecules to increase the reactant concentration, also can promote C-C coupling through photoelectric synergism. This work provides a favorable reference for the rational design of photocathodes by confinement effect of porous structure.