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 N 2 under ambient conditions. Herein we report for the first time on visible-light-assisted photocatalytic nitrogen fixation by metal organic framework material at room temperature and pressure. The Ti 3+ species induced by electron transfer from ligand-to-metal charge transfer process provide active sites for N 2 reduction. Furthermore, visible-light-assisted photocatalytic N 2 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 NH 2 -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 light-harvesting and catalytic components in a single solid platform for green NH 3 production.
To reduce the emission of NO from fossil fuel combustion and the energy consumption associated with NH3 production, the development of simple and efficient methods to transform NO into high-value-added NH3 is essential. Here, we report the efficient catalytic hydrogenation of NO to NH3 under mild reaction conditions by the synergistic catalysis of functionalized ionic liquids (FILs) and Pd catalysts. In this system, an FIL [TEPA][Im] acted as both an absorbent and a catalyst. The presence of [TEPA][Im] enhanced the catalytic performance by changing the coordination and electronic environment of Pd on the Pd/C catalyst. First, NO was absorbed by [TEPA][Im]; then, the hydrogenation of absorbed NO to NH3 was performed at a low temperature via the synergistic catalyzation of [TEPA][Im] and Pd/C. The effects of various factors on NO hydrogenation to NH3 were also investigated. Remarkably, Pd/C exhibited outstanding properties in the formation of NH3 with a high yield of 67% in the FIL [TEPA][Im] under the conditions of 100 °C and an H2 pressure of 0.5 MPa. [TEPA][Im] could be reused multiple times and the product NH3 could be recovered by flashing.
危险品化学品经营许可证（带存储）