Improved photocatalytic degradation of malachite green with a novel composite β-bihydroxycobalt phthalocyanine/Cu-BTC

Abstract In this work, a novel MOF (metal organic framework) based composite of β-BCoPc/Cu-BTC is fabricated by immobilizing β-aryloxy phthalocyanine cobalt (β-BCoPc) on Cu-BTC (benzenetricarboxylic acid-Cu) via a facile impregnation approach. After a systematic characterization via X-ray diffraction, X-ray photoelectron spectroscopy, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and N2 adsorption–desorption isotherms, the above-synthesized catalyst is for the first time applied to photocatalytically decompose refractory malachite green (MG) dye pollutant under UV light irradiation. In comparison with that of the β-BCoPc or Cu-BTC monomers, the synthesized β-BCoPc/Cu-BTC composite shows a significantly enhanced photocatalytic degradation performance of MG with a best degradation efficiency up to 90.12 %, which can easily be attributed to the synergistic effect between the Cu-BTC and β-BCoPc effectively improving light utilization efficiency, accelerating charge transportation and reducing charge recombination due to the desirable properties such as the conjugacy of the MOFs skeleton, the positive catalytic activity of central ion and large specific surface area, etc. In conclusion, the present work provides an effective and novel strategy via preparing MOF-based composite catalyst to realize the photocatalytic degradation of MG.