Enhanced Nitrogen Photo Fixation Performance of Transition Metal-Doped Urchin-Like W18O49 Under Visible-Light Irradiation

Nitrogen photo fixation mediated by various photocatalysts has received extensive concerns in recent years. In this work, a general strategy is proposed to enhance nitrogen photo fixation performance with some W18O49-based photocatalysts under visible-light irradiation. A series of photocatalysts were successfully synthesized in the presence of some noble-metal-free transition metals (Fe, Co and Ni) to modify the urchin-like W18O49. The resulting photocatalysts were systematically characterized using XRD, SEM, EDS, XPS, PL, N-2 adsorption-desorption isotherms, and DRS. Structural characterization of the photocatalysts revealed that the crystal morphology features were preserved, optional harvesting properties were enhanced, BET specific surface area was extended, and migration efficiency of the photo-induced charge carriers was significantly improved in the modified-W18O49 materials. Therefore, a progressed nitrogen photo fixation performance was observed. The maximum production of NH4+ was approximately reached to 2752 mu g.g(-1) catal. under the optimum reaction conditions. Furthermore, a plausible nitrogen photo fixation mechanism in the presence of the synthesized composites is also proposed.