One-step fabrication of Cu-doped Bi2MoO6 microflower for enhancing performance in photocatalytic nitrogen fixation.

Cu-doped Bi 2 MoO 6 microspheres were synthesized via a simple solvothermal method and exhibited much higher activity than pure Bi 2 MoO 6 for photocatalytic N 2 fixation due to their elevated Femi level, conduction band position, and charge separation efficiency. [Display omitted] This study enhances the photocatalytic N 2 immobilization performance of Bi 2 MoO 6 through Cu doping. Cu-doped Bi 2 MoO 6 was synthesized via a simple solvothermal method. Various characterizations were implemented to examine the influence of Cu doping on the properties of Bi 2 MoO 6. Results indicated that the doped Cu element had a valence state of + 2 and substituted the position of Bi3+. Cu doping exerted minimal effect on the morphology of Bi 2 MoO 6 but largely influenced the energy band structure. The band gap was slightly narrowed, and the conduction band was raised, such that Cu-doped Bi 2 MoO 6 could generate more electrons with stronger reducibility. Moreover, importantly, Cu doping reduced work function and improved charge separation efficiency, which was considered the major cause of enhanced photoactivity. In addition, the Cu-Bi 2 MoO 6 catalyst exhibited higher capability in the adsorption and activation of N 2. Under the combined effects of the aforementioned changes, Cu-Bi 2 MoO 6 demonstrated considerably higher photocatalytic efficiency than Bi 2 MoO 6. The optimized NH 3 generation rate reached 302 μmol/L g−1h−1 and 157 μmol/L g−1h−1 under simulated solar light and visible light, respectively, both achieving about 2.2 times higher than that of Bi 2 MoO 6. This work provides a successful example of improving photocatalytic N 2 fixation, and it may show some light on the design and preparation of heteroatom-doped semiconductor photocatalysts for N 2 -to-NH 3 conversion. [ABSTRACT FROM AUTHOR]