Outstanding photocatalytic nitrogen fixation performance of TiO2 QDs modified by Bi2O3/NaBiS2 nanostructures upon simulated sunlight

Nowadays, a promising material for NH3 production under mild and safe conditions using heterogeneous photocatalysts is very important. In this regard, Bi2O3 and NaBiS2 nanoparticles were combined with TiO2 quantum dots (QDs) through a facile hydrothermal process. The TiO2 QDs/Bi2O3/NaBiS2 nanocomposites displayed excellent performance in the photofixation of nitrogen upon simulated sunlight. The NH3 generation rate constant over the optimum nanocomposite was 10.2 and 3.3-folds higher than TiO2 (P25) and TiO2 QDs photocatalysts, respectively. The spectroscopic and electrochemical studies affirmed more effective segregation and transfer of photo-induced charge carriers within ternary nanocomposite, due to the developing tandem n-n-p heterojunctions, which led to more lifetime of charges. Moreover, the impacts of solvent, pH, electron scavenger, and lake of nitrogen molecules on the NH3 generation were investigated. Finally, it was concluded that the TiO2 QDs/Bi2O3/NaBiS2 nanocomposite, with appealing features of more activity, high stability, and a facile one-pot synthesis method, is a promising photocatalyst in nitrogen fixation technology.