Novel n-n heterojunction nanocomposite constructed by g-C3N4 nanosheets and Cu3V2O8 nanoparticles: Facile fabrication and improved photocatalytic activity for N2 fixation under visible light

The production of ammonia in the nitrogen cycle plays an essential role in sustaining life. Recently, clean and efficient photocatalytic processes for the synthesis of ammonia from nitrogen under mild conditions have been considered. However, progress in the design of efficient photocatalysts operating in the visible region for the nitrogen fixation reaction remains a challenge. For the first time, a novel visible-light-driven g-C3N4 nanosheet/Cu3V2O8 photocatalyst with prominent photocatalytic nitrogen fixation ability was synthesized by a facile calcination synthetic method. The purity, morphology, crystallinity, optical property, and chemical composition of prepared samples were investigated by XRD, FT-IR, DRS, PL, FESEM, TEM, HRTEM, EDX, XPS, and photoelectrochemical techniques. The g-C3N4 nanosheet/Cu3V2O8 nanocomposite exhibited an outstanding improved photocatalytic ammonium generation of 3850 μmol L−1 g−1, which was 2.6 and 4.3 times higher than that of g-C3N4 nanosheet and Cu3V2O8. The positive effect of n-n-heterojunction formation increased photocatalytic activity through the built-in electric field between g-C3N4 nanosheet and Cu3V2O8, transferring electron-hole pairs and extending the life of charge carriers. High efficiency and reusability of the photocatalyst after 5 consecutive tests show the prepared nanocomposite potential for large-scale photocatalytic processes.