Promotion of CO2 reduction in a nanophotocatalyst by hydrogen peroxide

Abstract

Based on environmental concerns and the worldwide energy crisis, CO2 photoreduction into value-added chemicals has attracted considerable attention. However, insufficient reducing forces remain a key challenge. A nanophotocatalyst, constructed by synchronously embedding formate dehydrogenase and CdS into a zeolitic imidazolate framework, promotes CO2 photoreduction by relying on photo and chemical reducing forces. Hydrogen peroxide (H2O2) can replace water (H2O) to provide protons and electrons for CO2 photoreduction. Compared with adding reduced nicotinamide adenine dinucleotide (NADH) only, the yield of formic acid and the maximum catalytic rate increased by 2.78 and 2.55 times with adding NADH and H2O2 together as a reducing force. Protons and electrons from photolyzed H2O2 as a chemical reducing force and CdS as a photo reducing force together promote the cofactor regeneration, which in turn enhances CO2 photoreduction. This work is expected to guide a simple green method for promoting CO2 photoreduction to prepare value-added chemicals and solar fuels.