Environmentally Benign Hybrid Polyvinylidene Fluoride/Si‐12‐Tungstophosphoric Acid Membranes with Catalytic Activity for Dye Degradation Under Light and Dark Conditions

Abstract A catalytically active membrane can facilitate both chemical reactions and membrane separation. In this study, a novel hybrid membrane was fabricated via electrospinning by incorporating 12‐tungstophosphoric acid (TPA), a Keggin‐structured compound, and tetraethyl orthosilicate (TEOS) into polyvinylidene fluoride (PVDF). TEOS enabled effective interaction between TPA and PVDF, enhancing structural stability. The membrane was applied for the catalytic degradation of organic pollutants and characterized using FTIR, FESEM, Raman spectroscopy, TGA, XPS, and XRD. XPS confirmed the incorporation of TPA, while FTIR, Raman, XRD, and TGA demonstrated strong filler–matrix interactions through Si─O─C bonding, improved crystallinity, and reduced thermal degradation temperature. FESEM analysis showed reduced fiber diameter with TPA addition, contributing to increased surface area. The membrane's catalytic performance was tested using cationic dyes—methylene blue (MB) and rhodamine B (RhB)—under both dark and light conditions, supported by kinetic studies. The PVDF membrane containing 15 wt% TPA showed nearly complete degradation, achieving 96% under light and 87% in the dark. These findings highlight the PVDF/Si‐TPA hybrid membrane as a promising, multifunctional material for efficient dye degradation under both photo‐assisted and dark catalytic conditions.