Promotion of CO₂ reduction in a nanophotocatalyst by hydrogen peroxide

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.