ZIF-67 with Argon annealing treatment for visible light responsive degradation of organic dyes in a wide pH range

Zeolite imidazolate frameworks (ZIFs) are a novel kind of zeolite materials with regular porous network structures, belonging to mental-organic frameworks (MOFs). Thanks to their high porosity and large specific surface area , ZIFs could have potential applications in the field of photocatalysis . In this paper, visible light responsive photocatalyst of ZIF-67 was synthesized by a one-step hydrothermal method under a mild condition. We explored three organic dyes in aqueous solutions were degraded under visible light irradiation . And corresponding photocatalytic performances of ZIF-67 with controllable synthetic conditions were evaluated systematically. It was found that ZIF-67(9 h) had the highest degradation efficiency. Besides, the ZIF-67(9 h) were heated in Ar can maintain their crystal structure and microporous form, but exposed more sites to improve photocatalytic activity with partial bond breakage . More than 75% methyl orange (MO), 85% methyl blue (MB) and 54% Rhodamine B (RhB) can be degraded with a 0.5 g L −1 ZIF-67(9 h)(Ar) under visible light irradiation. Moreover, the ZIF-67(9 h)(Ar) demonstrates a strong pH changing tolerance in both acid and alkaline aqueous solutions, the degradations can be well performed in a wide pH range from 3.0 to 11.0.