Construction of Low-Cost Z-Scheme Heterojunction Cu₂O/PCN-250 Photocatalysts Simultaneously for the Enhanced Photoreduction of CO₂ to Alcohols and Photooxidation of Water

Solar-driven high-efficiency conversion of CO 2 with water vapor into high-value-added alcohols is a promising approach for reducing CO 2 emissions and achieving carbon neutrality. However, the rapid recombination of photogenerated carriers and low CO 2 adsorption capacity of photocatalysts are usually the factors that limit their applicability. Herein, a series of low-cost Z-scheme heterostructures Cu 2 O/PCN-250- x are constructed by in situ growth of ultrasmall Cu 2 O nanoparticles on PCN-250. A systematic investigation revealed that there is a strong interaction between Cu 2 O nanoparticles and PCN-250. The resulting Cu 2 O/PCN-250-2 exhibits excellent photogenerated carrier separation efficiency and CO 2 adsorption capacity, which dramatically promote the conversion of CO 2 into alcohols. Notably, the total yield of 268 μmol g cat –1 for the production of CH 3 OH and CH 3 H 2 OH is superior to that of isolated PCN-250 and Cu 2 O. This study provides a new perspective for the design of a Cu 2 O nanoparticle/metal–organic framework Z-scheme heterojunction for the reduction of CO 2 to alcohols with water vapor.