SnO2 Nanoparticle-Dispersed, Phosphoric Acid-Doped Poly(vinyl alcohol)/Epoxy Resin/Siloxane Hybrid Network Proton Transport Membrane for Fuel Cell Applications

The sol–gel approach was used successfully to synthesize the poly(vinyl alcohol)/epoxy resin/3-aminopropyl triethoxysilane (PVA/Ep/APS) membrane, through dialdehyde, epoxy, and 3-aminopropyl triethoxysilane, cross-linking of PVA, and the doctor blade method was used to generate the thin film. The current study focuses on the proton conductivity and suitability of a hybrid network membrane made of PVA/Ep/APS and SnO2 nanoparticles (NPs) (SnO2/PVA/Ep/APS) toward polymer electrolyte fuel cell. The polymer mix with 0.5 and 1.0% Ep/APS in PVA had a higher ion exchange capacity (IEC) value (0.57 and 0.79 mmol/g) than that of the film made entirely of PVA (0.32 mmol/g). However, PVA/Ep/APS/SnO2 (1%) has a low IEC of 0.92 mmol/g, whereas PVA/Ep/APS/SnO2 (2% and 3%) had IEC values of 1.19 and 1.32 mmol/g, respectively. However, the inclusion of SnO2 NPs increased the PVA/Ep/APS membrane's capacity to absorb water (1, 2, and 3%). The incorporation of SnO2 NPs decreased the swelling ratio of PVA/Ep/APS, and the degree of water absorption of PVA/Ep/APS reduced the swelling ratio significantly. The proton conductivity of the PVA/Ep/APS sheets is better than that of the membrane manufactured from unmodified PVA. Notably, the stability of the membrane has been increased in the SnO2 NPs dispersed in a 3% PVA-blended membrane by 29.80%. It has been demonstrated that the PVA/Ep/APS nanocomposite films with incorporated SnO2 NPs have higher proton conductivities than that of PVA/Ep/APS alone. The 3% SnO2-loaded membrane, which measured 2.27 × 10–2 S/cm at 110 °C, was shown to have a greater proton conductivity than those of other PVA mix membranes. PVA/EP/APS-blended membranes are potential membrane materials for fuel cells according to the results.