Photodegradation Of Bisphenol A In Water Via Round-The-Clock Visible Light Driven Dual-Layer Hollow Fiber Membrane Incorporated With Tungsten Nanotubes

Bisphenol A (BPA) is an endocrine-disrupting chemical harmful to human health. Photocatalytic degradation using visible-light photocatalysts with energy storage capability enhances BPA removal. However, WO ₃ -based photocatalysts face limitations due to constrained active sites and less efficient charge transfer. To address these issues, novel Cu ₂ O/WO ₃ nanotubes (CWNT) were developed, offering large surface areas that improve charge carrier dynamics and photocatalytic activity. WO ₃ stores reductive energy during light irradiation, while Cu ₂ O functions as a visible-light photocatalyst due to its low band gap of 2.2eV. The Z-scheme heterojunction between WO ₃ and Cu ₂ O enables synergistic effects. A dual-layer hollow fibre (DLHF) membrane embedded with CWNT was developed for BPA degradation through photocatalysis and energy storage. CWNT was synthesized, and increased Cu ₂ O loading enhanced photocatalytic efficiency, with CWNT-L10 achieving the best degradation (85% under light, 70.73% in the dark), leading to its selection for membrane fabrication. The DLHF membrane was fabricated with varying CWNT loadings. The membrane with 5wt% CWNT loading (PVDF-L0.5) showed superior performance, significantly enhancing hydrophilicity, surface roughness, porosity, and mechanical strength over the neat membrane. PVDF-L0.5 exhibited high BPA degradation rates (97% under light, 77.60% in the dark) and a high water flux of 534 ± 5.18L/m²·h. Compared to non-nanotube photocatalysts, it showed a 2.6% higher BPA removal efficiency. PVDF-L0.5 maintained performance over three cycles with a low efficiency drop of 12.43%. Leaching tests showed no Cu and minimal W leaching, indicating environmental safety. This study demonstrates the potential of CWNT-embedded DLHF membranes with energy storage capability for efficient BPA degradation in wastewater treatment.