Integration of rod-shaped PCN-224(Cu) and BiVO4 to establish S‑scheme heterojunction for effective photocatalytic CO2-to-CO transformation

Abstract

The search for effective and highly selective photocatalysts for CO2 transformation is exceptionally desirable yet challenging. Herein, a novel BiVO4@PCN-224(Cu) heterostructure was constructed by growing BiVO4 nanosheets on the surface of PCN-224(Cu) rods for visible-light-driven CO2 photoreduction. The obtained BiVO4@PCN-224(Cu) heterostructure could selectively reduce CO2 into CO in the absence of sacrificial reagents. The CO yield over the optimized sample reached 70.5 μmol g-1 h-1 (corresponding to an apparent quantum yield of 0.42% at 450nm), a 5.1-fold increase over pristine PCN-224(Cu). The boosted activity of the hybrid could be credited to the S-scheme heterojunction formed at the interface of PCN-224(Cu) and BiVO4, which facilitated the separation of photogenerated charges and ameliorated the redox capability. In-situ XPS and hydroxyl radical determination confirmed the S-scheme charge transfer mode. This study provides a new strategy for constructing S-scheme heterojunctions involving metalloporphyrin-based metal-organic frameworks for high-performance CO2 conversion.