In-Situ Construction of G-C3n4/Lapo4 S-Scheme Heterostructure with Nitrogen Vacancy for Boosting Photocatalytic Reduction of Co2

Abstract

It is a realizable way to enhance the performance of photocatalytic reduction of carbon dioxide by constructing S-scheme heterojunctions due to its unique interfacial structures. In this article, g-C3N4/LaPO4 heterojunctions with surface nitrogen vacancies were prepared by in-situ one-pot hydrothermal method. The experimental results show that the generation rate of carbon monoxide produced via the best g-C3N4/LaPO4 heterojunction is 145.8μmol g-1 h-1, which is 4.0 times and 11.2 times as large as pure g-C3N4 and LaPO4, respectively. The heterojunction structure is characterized by UPS, in situ XPS and DFT calculation. The construction of S-scheme heterojunction can efficiently promote the separation of photogenerated electron holes and improve the redox capacity to boost photocatalytic activity. Furthermore, nitrogen vacancy in g-C3N4/LaPO4 heterojunction could provide more reaction active sites, which is conductive to the absorption, distribution and activation of CO2 and H2O molecules. In conclusion, this advancement offers a promising direction for the development of more effective photocatalytic materials for environmental and energy-related applications.

Keywords: S-scheme heterojunctions, Nitrogen vacancy, CO2 reduction, Photocatalytic mechanism