Integration of 3D macroscopic graphene aerogel with OD-2D AgVO3-g-C3N4 heterojunction for highly efficient photocatalytic oxidation of nitric oxide

The application of three-dimensional (3D) aerogels for immobilizing powder catalysts can greatly enhance the catalyst cycling stability. In this study, we modify two-dimensional (2D) graphitic carbon nitride (g-C3N4) nanosheets with zero-dimensional (0D) silver metavanadate (AgVO3) quantum dots. The resulting 0D-2D hetero-junction facilitates the separation of electron-hole pairs, and exhibits high efficiency for removing nitric oxide (NO) at low concentrations (600 ppb) at room temperature. The removal efficiency is much higher than that of pure g-C3N4. The porous network framework of the 3D AgVO3-g-C3N4-graphene hybrid aerogel is formed by bridging of graphene oxide sheets. This results in the heterojunction further enhancing electron-hole separation. The modification of g-C3N4 promotes the separation of photogenerated carriers in a step by step manner, and enhances their oxidation-reduction ability. The AgVO3-g-C3N4-graphene hybrid aerogel exhibits excellent catalytic activity for NO removal (maximum of 65%). Cycling experiments verify the stability and recyclability of the aerogel.