2D/2D Bi2MoO6/g-C3N4 direct Z-scheme Van der Waals heterojunction photocatalyst for boosting nitrogen fixation

Although photocatalytic nitrogen fixation is an efficient and environmentally-friendly technology for ammonia synthesis, it still faces challenges such as high recombination of photo-generated carriers and a lack of active sites for the reaction of catalysts. Constructing direct Z-scheme heterojunctions is considered an effective strategy to enhance carrier separation efficiency of catalysts. However, it still encounters the challenge of lacking surface active reaction sites. The 2D Z-scheme Van der Waals heterojunction has the same charge transfer mechanism of direct Z-scheme heterojunctions, ensuring high carrier efficiency and retaining strong redox ability. Additionally, its layered structure provides a large number of reactive sites. In this study, theoretical calculation simulation was employed to predict the properties of Bi2MoO6 (BMO) and g-C3N4 (CN), and to simulate the dynamic behavior of photogenerated carriers. A 2D/2D CN-BMO direct Z-scheme Van der Waals heterojunction was constructed. Remarkably, this heterojunction demonstrated significantly enhanced photocatalytic ammonium generation capabilities. This study provides valuable insights for the development of advanced heterojunction photocatalysts.