Preparation and photocatalytic activities for decomposition of methylene blue of zeolitic imidazolate framework-8

Abstract

In the present study, zeolitic imidazolate framework-8 (ZIF-8) is synthesized quickly in methanol solvent with the support of ultrasound, and application of photocatalyst for methylene blue (MB) decomposition reaction under UV radiation. The obtained ZIF-8 was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and UV-Vis diffuse reflectance spectra (DR-UV-Vis). The influence pH and kinetics of photocatalytic MB decomposition and reusability of ZIF-8, were also investigated. The results indicated that ZIF-8 could work effectively in the wide pH range from 4 to 12. When the initial pH of the solution increases to 12, the adsorption capacity and MB decomposition efficiency are both high. The MB decomposition on the ZIF-8 photocatalyst followed a pseudo-first-order kinetics model. The structural strength of ZIF-8 as well as the relatively high photocatalytic efficiency after reuse three times shows that ZIF-8 has good reusability and can be applied to treatment of organic pollutants in aqueous solution.