LAUSR

The construction of high performance photocatalyst has always been explored. Covalent organic frameworks (COFs), especially keto-amine linked COFs, have many advantages, such as adjustable band gaps, π-π stacking structure, excellent response ability to visible light, high specific surface area, high mobility of carrier carriers, good physical and chemical stability, etc, which is showing strong potential applications in photocatalytic solar energy conversion and hydrogen production. Two analogous covalent triazine frameworks (CTFs) including T3H-CTF and T3N-CTF have been synthesized via Schiff-base condensation reactions between 2,4,6-trihydroxybenzene-1,3,5-tricarbalehyde (MOP) with the corresponding triazine based aromatic amines under solvothermal condition. For T3N-CTF, the peripheral aromatic linker to the central triazine unit is the pyridine unit, instead of the benzene unit in the T3H-CTF unit. T3N-CTF has a hydrogen production rate (HPR) of 6485.05 μmol g -1 h -1 , much higher than that of T3H-COF (2028.06 μmol g -1 h -1 ). Accordingly, T3N-CTF has a much higher apparent quantum yield (AQY) of 12.2% than that of T3H-CTF (4.12%) at 405 nm. The experimental and theoretical results showed that the extended light absorption range, enlarged surface area, and enhanced separation and transportation efficiencies of charge carriers of T3H-COF than that of T3H-CTF are uniformly induced by the introduction of peripheral nitrogen atoms into the skeleton of former CTF, which eventually boosting the visible-light induced hydrogen evolution reaction (HER).