Hao Huang, Xu-Sheng Wang, Davin Philo, Fumihiko Ichihara, Hui Song, Yunxiang Li, Dan Li, Teng Qiu*, Shengyao Wang*, Jinhua* 

ABSTRACT: The fixation of atmospheric dinitrogen to ammonia is one of the most essential processes for sustaining life. Since the N^N bond in dinitrogen is one of the strongest bonds in chemistry, it remains a grand challenge to develop efficient catalysts for fixation of N2 under ambient conditions. Herein we report for the first time on visible-lightassisted photocatalytic nitrogen fixation by metal organic framework material at room temperature and pressure.The Ti3+ species induced by electron transfer from ligand-to-metal charge transfer process provide active sites for N2 reduction. Furthermore, visible-light-assisted photocatalytic N2 fixation is achieved by ligands functionalization which extend the light harvesting of the MOF to visible region. The integration of Ti sites and amine-functionalized linkers in NH2-MIL-125 (Ti) shows the highest visible light photocatalysis efficiency at a rate of 12.3 μmol g−1 h−1. This Ti MOF system therefore shows a potential as a new design of combining lightharvesting and catalytic components in a single solid platform for green NH3 production.

KEYWORDS:Metal organic framework, Ligand design, Photocatalysis, Nitrogen fixation