Bifunctional phosphate-modulated Cu2O/CeO2 redox heterojunction: A promising approach for proficient CO2 reduction

The construction of extremely dispersed redox-heterojunctions is a critical step toward improving of photo catalytic activity. Nonetheless, electron transfer faces momentous hurdles at the interfaces of these redoxheterojunction, mainly as a result of the considerable gap and potential-barrier between them. To address this obstacle, a bifunctional phosphate was deliberately introduced as an electron-bridge into the Cu2O/CeO2 redoxheterojunction system, aiming to necessitate a potential-barrier, establish a photoelectron transport route to improve the surface catalysis, and serve as a catalyst stabilizer, leading to improved dispersion of Cu2O on the CeO2 surface. The resultant intricately dispersed and optimized redox-heterojunction showcased an unparalleled advancement in apparent quantum efficiency (AQE), attaining an approximate value of 1.41 % at 420 nm during the photocatalytic CO2 reduction. The experimental findings established a conspicuous association between the substantial increase in AQE and the diminished interfacial migration resistance, heightened dispersion, and abundance of more active-sites, all accredited to phosphate-modulation in the redox-heterojunction. The work emphasizes the significant importance of phosphate in bridging the conduction and valence bands of semiconductors, leading to enhanced photocarrier separation efficiency and improved molecular dispersion.

Automated summary

The construction and optimization of redox-heterojunctions using a bifunctional phosphate as an electron-bridge demonstrated significant improvements in photo catalytic activity, including enhanced dispersion, reduced interfacial migration resistance, and increased abundance of active-sites.