Single-Atom Mo Supported by TiO₂ for Photocatalytic Nitrogen Fixation

The challenge of achieving efficient photocatalysts for the fixation of ambient nitrogen to ammonia persists. The utilization efficiency of single-metal-atom catalysts leads to an increased number of active sites, while their distinctive geometrical and electronic characteristics contribute to enhancing the intrinsic activity of each individual site. In this study, we present a method using an organic molecule to assist in loading TiO₂ with Mo single atoms for the purpose of photocatalytic nitrogen fixation. By adjusting the number of Mo single atoms loaded, we were able to regulate the microenvironment surrounding the catalytic center. Our results demonstrate that TiO₂-Mo10 achieved a remarkable photocatalytic nitrogen fixation performance of 42.05 μmol·g^-1·h^-1 at room temperature while maintaining excellent structural stability and cycle life. The incorporation of Mo single atoms effectively enhanced electron separation and migration within TiO₂, leading to a significant weakening of the N≡N bond. This research highlights the potential for predesigning TiO₂-based single-atom photocatalysts with tailored structures for efficient nitrogen fixation through photocatalysis. These findings offer valuable insights for the future development and rational design of single-atom photocatalysts.