Studies On Preparation Of P/Si Glass-Based Proton Exchange Membranes (PEMS) And Their Pem Fuel Cell Performance

Proton Exchange Membrane Fuel Cell (PEMFC) has attracted great interest due to its high energy conversion efficiency, high energy density, and good environmental compatibility. The proton exchange membrane (PEM) electrolyte is the key material in the PEMFC.Up to now, polymer electrolyte membranes, typically Nafion(?) are used most frequently in the current PEMFC, because they are characterized with high proton conductivity and reasonable chemical and mechanical stability. However, these membranes are expensive and low thermal stability and are susceptible to deformation due to adsorption and desorption of water. It is highly desired to develop novel glass-based electrolyte membranes with high proton conductivity and low costs.In this study, we report monolithic and transparent phosphosilicate membranes (PSMs) for high proton conduction. The membrane material was derived from the sol-gel precursors of tetraethoxy silane (TEOS) and orthophosphoric acid (H3PO4), which were subjected to hydrothermal treatment at 150℃for 30 h. The obtained PSMs exhibited proton conductivities of up to 10-1 S cm-1, which is comparable to those of available commercial membranes, such as a Nafion(?) membrane. The H2/air fuel cell equipped with the prepared glass membrane shows a power density of 20.8 mWcm-2.Furthermore, mixing the PVA and PVDF with phosphosilicate respectively, the PVA-doped and PVDF-doped phosphosilicate composite membranes have been prepared. The proton conductivities of both composite membranes were able to reach 10-2 S/cm, and both composite membranes have great flexibility and strength. The open circuit potential of the hybrid PVDF membrane was 0.99V in the H2/O2 fuel cell measurement. The maximum output power density of H2/air fuel cell equipped with the hybrid PVA membrane was only 8.19 mWcm-2.