Electrically conductive TiO2/CB/PVDF membranes for synchronous cross-flow filtration and solar photoelectrocatalysis

Mouheb Sboui; Wenke Niu; Gui Lu; Kai Zhang; Jia Hong Pan

doi:10.1016/j.chemosphere.2022.136753

Electrically conductive TiO₂/CB/PVDF membranes for synchronous cross-flow filtration and solar photoelectrocatalysis

Chemosphere. 2023 Jan:310:136753. doi: 10.1016/j.chemosphere.2022.136753. Epub 2022 Oct 7.

Authors

Mouheb Sboui¹, Wenke Niu², Gui Lu³, Kai Zhang⁴, Jia Hong Pan⁵

Affiliations

¹ Beijing Key Laboratory of Novel Thin Film Solar Cells, North China Electric Power University, Beijing, 102206, China; College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
² Beijing Key Laboratory of Novel Thin Film Solar Cells, North China Electric Power University, Beijing, 102206, China.
³ Beijing Key Laboratory of Novel Thin Film Solar Cells, North China Electric Power University, Beijing, 102206, China; School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing, 102206, China. Electronic address: lugui@ncepu.edu.cn.
⁴ School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing, 102206, China.
⁵ Beijing Key Laboratory of Novel Thin Film Solar Cells, North China Electric Power University, Beijing, 102206, China; College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China; Department of Chemistry and Centre for Processable Electronics, Imperial College London, White City Campus, London, W12 0BZ, UK. Electronic address: pan@ncepu.edu.cn.

PMID: 36216114
DOI: 10.1016/j.chemosphere.2022.136753

Abstract

Combining photocatalysis (PC) and membrane filtration (MF) has emerged as an attractive technology for water purification, however, the water purification efficiency and membrane fouling are still challenging. Herein, we report a novel photoelectrocatalytic (PEC) membrane mediated by a ternary polyvinylidene fluoride (PVDF)-carbon black (CB)-TiO₂ composite conductive membrane synthesized by a phase inversion method assisted by the mixed surfactants of polyvinylpyrrolidone (PVP) and sodium dodecyl sulfate (SDS). The resultant electrically conductive TiO₂/CB/PVDF membrane features a homogeneous surface with obvious pore size of 20-150 nm, a thickness ∼116 μm, and an average resistivity as low as ∼3.165 Ω∙m. The cooperation of PVP and SDS surfactants dramatically improves the organic-inorganic interactions and thus eventually enhances the porosity, stability of porous structure, mechanical stability, and conductivity and electrochemical properties of the hybrid membrane. Upon the solvent evaperation of the wellblended casting solution and the phase inversion, TiO₂/CB preferentially exist on the surface of PVDF membrane, enabling the efficient PEC degradation of organic pollutants. The synergistic coupling of TiO₂ and CB in PVDF membrane results in efficient PEC properties with bi-functional membrane antifouling and enhanced water purification in azo dyes decolorization under the stationary mode and in our lab-made continuous cross-flow PEC system, superior to those by photocatalysis and electrocatalysis. The developed synchronous MF and PEC system mediated by the conductive TiO₂/CB/PVDF membrane proves to a feasible route to improving the self-cleaning properties of the polymer membrane while simultaneously increasing the water decontaminating efficiency.

Keywords: Dye wastewater treatment; Hybrid conductive materials; Membrane filtration; Photoelectrocatalysis; Solar energy utilization; TiO(2) semiconductor photocatalysis.