Designing ultrathin Fe doped TaO nanobelts for highly enhanced ammonia photosynthesis.

Solar-light photosynthesis of ammonia form N reduction in ultrapure water over the artificial photocatalysts is attractive but still challenging compared with Haber-Bosch process. In this work, ultrathin Fe-TaO nanobelts were fabricated via the controllable solvothermal process for ammonia photosynthesis. The formed oxygen vacancies and Fe doping narrowed their bandgap energies and promoted the carriers' separation and transfer for Fe-TaO nanobelts. In addition, Fe doping also resulted in the reduced working functions of the samples, indicating a weaker electron binding restriction and stronger separation and transfer of photo-induced carriers. The experimental results showed that Fe-TaO nanobelts showed remarkably enhanced photocatalytic ammonia production performance under simulated sunlight irradiation, and the relevant ammonia production rate reached approximately 3030.86 μM g h, which was 9.63 times of pristine TaO and 491.0 times of commercial TaO, and a relatively stable photocatalytic ammonia production performance under simulated sunlight irradiation for Fe-TaO nanobelts. Meanwhile, it was also found that Fe doping has great influences on the photocatalytic performance under visible light and simulated sunlight irradiation, mainly because of their suitable bandgap energies and enhanced solar-light harvesting capacity. Current work indicates the great potentials of ultrathin tantalum-based functional materials for high-efficiency ammonia photosynthesis.