Photo(electro)catalytic Nitrogen Fixation: Problems and Possibilities

Abstract Photo(electro)catalytic nitrogen fixation is considered as a competing alternative for the Haber–Bosch (HB) process due to the direct production of ammonia (NH 3 ) from nitrogen and water with zero carbon dioxide emission, which has made it a very hot research topic in recent years. Particularly, photo‐driven nitrogen reduction has been attracted to a specific focus in the scientific community since it can be powered by limitless solar energy at ambient conditions. However, unsolved challenges have remained to date such as, electron–hole separation, low quantum efficiency, weak visible light harvesting, catalytic selectivity, N 2 adsorption, and activation. In this Review, the recent achievements and related approaches toward nitrogen fixation are presented. In addition, the discussions on mechanistic photofixation of nitrogen, catalytic engineering design, and the outlook for enhancing the photocatalytic performance of ammonia photosynthesis are also devoted. Finally, the emerging trend of advanced photo(electro)catalysts for nitrogen fixation is proposed.