Constructing the multilayer O-g-C3N4@W18O49 heterostructure for deeply photocatalytic oxidation NO

Suffering from inefficient separation and transfer of photogenerated carriers, the deeply photocatalytic oxidation of NO-to-NO3- over g-C3N4 is still a daunting challenge. Well-designed heterojunction photocatalysts have been proven to be effective in steering charge transfer for achieving a particular migration path and more active sites, which hold huge promise in further performance stimulation. Herein, in-situ face-to-face hydrothermal approach is developed to prepare a multilayer heterostructure O doping g-C3N4 (O-g-C3N4) with W18O49 (O-g-C3N4@W18O49). The experimental and theoretical results show that the unique multilayer heterostructure can improve the separation efficiency of carriers by changing the electron migration path. Moreover, doping O atoms are identified as the newly formed active centers to largely facilitate the activation of NO. Impressively, the O-g-C3N4@W18O49 photocatalyst thus exhibits largely improved photocatalytic NO removal rate (56.7 %, 0.1 g of sample) and high selectivity of NO to NO3- (98.3 %). It outperforms the reported photocatalysts materials in visible light. This study not only provides a facile strategy for experimentally screening advanced photocatalytic materials, but also paves the way for the deep oxidation of NO.