A new composite membrane based on Keggin polyoxotungstate/poly(vinylidene fluoride) and its application in photocatalysis

摘要

Polyoxometalate (POM) is a promising candidate as a photocatalyst for the removal of organic pollutants from water, showing striking similarities to TiO2. However, the drawback of its high solubility in solution makes it difficult to recover and recycle, which impedes its potential applications in wastewater treatment. We have developed a new composite membrane based on Keggin POM and poly(vinylidene fluoride) (PVDF) via combining a doctor-blade method, immersion precipitation and colloid interface techniques. The as-prepared composite membrane was characterized by FTIR, SEM and X-ray EDS, revealing that the Keggin POM could be homogenously intermingled in the composite membrane. The composite membrane not only exhibits good degradability on methyl orange in the presence of H2O2 and excellent photocatalytic repeatability by maintaining 97.36% of the initial decolorization efficiency even after 8 cycles, but also can be easily handled and recycled.