Abstract: As an important carrier of clean energy, NH₃ is a necessary raw material for the production of various chemicals, which is closely related to the rapid development of human society. The photocatalytic nitrogen fixation technology has attracted extensive attention of researchers in recent years, since it uses clean solar energy as the only energy input toward directly converting N₂ and H₂O to NH₃ under mild conditions. Although the advantages of photocatalytic nitrogen fixation technology are environmentally friendly, energy conservation and easy to operate, the traditional semiconductor photocatalyst used for nitrogen fixation cannot fully exert its activity due to the restriction in light harvest and utilization of photogenerated carriers. In order to efficiently enhance the nitrogen fixation performance, thus, it is necessary to design the corresponding catalysts to improve the adsorption and activation of inert N₂ molecules. In this paper, first of all, a brief overview of photocatalytic nitrogen fixation was given and two possible reaction mechanisms of photocatalytic nitrogen fixation were introduced. Then, the focus was put on the influence of semiconductor materials containing oxygen, nitrogen and sulfur vacancies on photocatalytic nitrogen fixation. Finally, some practical opinions on the current challenges and future development in the field of photocatalytic nitrogen fixation were given.

Key words: semiconductor, photocatalytic, nitrogen fixation, defect, oxygen vacancy, nitrogen vacancy, catalytic mechanism, photogenerated carrier