Fe doped SrWO4 with tunable band structure for photocatalytic nitrogen fixation.

Doping with exotic elements has become a general effective method for the synthesis of efficient nitrogen fixation photocatalyst. Wide bandgap semiconductors, thermodynamically, could be potential photocatalysts for nitrogen reduction reaction (NRR). In this study, we report an active photocatalyst of Fe doped SrWO4 from a facile solvothermal method. The band structure of SrWO4 can be regulated by varying the Fe doping concentration, and still fulfill the thermodynamical requirements of photocatalytic NRR. The doped samples also exhibit strong absorbance in visible light region. At optimal doping concentration, the photocatalyst shows significant enhancement of the ammonia production rate in ultrapure water compared to the pristine SrWO4. The results photoelectrochemical measurements and the photoluminescence spectra indicate that the enhancement of the performance is ascribed to the balanced defect states and optimized charge transfer. The present study opens a route toward the development of active photocatalysts with preferable thermodynamics for the fixation of atmospheric N2 employing solar light.