Enhanced photocatalytic activity of zeolitic imidazolate framework-8 by modification with phosphor tungstic acid

Phosphor tungstic acid (PTA)-modified zeolitic imidazolate framework-8 (ZIF-8) catalysts were synthesized for photocatalytic degradation of methylene blue under UV irradiation. The as-prepared catalysts were characterized by the powder X-ray diffraction, N2 adsorption-desorption, Fourier transform infrared spectroscopy, Raman spectroscopy and UV-vis diffuse reflectance spectroscopy techniques. The optimum reaction conditions for photocatalytic degradation of methylene blue on the obtained materials were investigated. The results show that PTA evidently improved the activity of ZIF-8 catalysts because of its fast reversible multi-electron redox transformations. In addition, the reaction mechanism underlying the process was proposed.