  Photocatalytic nitrogen fixation is an important pathway for carbon
neutralization and sustainable development. Inspired by nitrogenase, the
participation of molybdenum can effectively activate nitrogen. A novel Ti/Mo
composites photocatalyst is designed by sintering the molybdenum
acetylacetonate precursor with TiO$_{2}$. The special carbon-coated hexagonal
photocatalyst is obtained which photocatalytic nitrogen fixation performance is
enhanced 16 times compared to pure TiO$_{2}$ at room temperature and ambient
pressure. The abundant surface defects in this composite were confirmed to be
the key factor for nitrogen fixation. The $^{15}$N$_{2}$ isotope labeling
experiment was used to demonstrate the feasibility of nitrogen to ammonia
conversion. Also, modelling on the interactions between light and the
synthesized photocatalyst particle was examined for the light absorption. The
optimum nitrogen fixation conditions have been examined, and the nitrogen
fixation performance can reach up to 432
${\mu}$g$\cdot$g$_{\text{cat}}^{-1}\cdot$h$^{-1}$. Numerical simulations via
the field-only surface integral method were also carried out to study the
interactions between light and the photocatalytic particles to further confirm
that it can be a useful material for photocatalyst. This newly developed Ti/Mo
composites provide a simple and effective strategy for photocatalytic nitrogen
fixation from air directly under ambient conditions.
