Visible-light responsive PVDF/carbon sphere@TiO2 membrane for dye scavenging and bacteria inactivation

Abstract

Titanium dioxide (TiO2) is wildly used for dye scavenging and bacteria inactivation in wastewater treatment. However, its photocatalytic efficiency is significantly limited by two inherent limitations including quick electron-hole pair recombination and wide bandgap energy (∼3.2 eV). In this work, we present a composite membrane that shows superior photocatalytic properties under visible light in dye scavenging and bacteria inactivation. The carbon sphere@TiO2 (CST) was manufactured via a two-step hydrothermal progress as a visible-light activated nano-photocatalyst and then electrospun with poly(vinylidene fluoride) (PVDF) to fabricate PVDF/CST composite membrane. When exposed to visible light, the PVDF/CST composite membrane performs well in terms of organic dye degradation. Furthermore, antibacterial activity assays show that the composite membrane has excellent sterilizing characteristics. Overall, this composite membrane appears to be a potential material for dye scavenging and bacterial inactivation in wastewater treatment.