SnO₂ Nanoparticle Assisted Enhanced Proton Exchange Membrane Fuel Cell Performance of Sulfuric Acid-Doped Porous Poly (Triphenylpyridine–Aliphatic Ethers)

A proton exchange membrane fuel cell (PEMFC) was fabricated with SnO 2 nanoparticles (NPs)-dispersed sulfuric acid-doped poly (triphenylpyridine aliphatic ether) (SPTPAEs) membrane and studied. The microporous SPTPAES membrane was successfully synthesized through a Chichibabin reaction (which is an aminative cyclization between the synthesized aliphatic chain containing aryl aldehydes and ketones without high cost metal catalysis) and SnO 2 NPs through a template-free, one-pot hydrothermal method and were further characterized using FTIR, NMR, atomic force microscopic, and TEM analysis. The typical properties of the bare SPTPAEs and 1, 2, 3, 5, 7, and 10% SnO 2 NP-embedded SPTPAE nanocomposite (NC) membranes, such as swelling ratio (SR), water uptake (WU), porosity, ion exchange capacity (IEC), proton conductivity (PC), and oxidative stability, were evaluated. The powder X-ray diffraction pattern suggested the successful formation of an amorphous natured polymer and the tetragonal rutile-structured SnO 2 NPs. The scanning electron microscopy and AFM images indicated that the SPTPAE polymer film has a uniform porous morphology. The 10% SnO 2 NP-loaded SPTPAE NC membrane exhibited an IEC value of 1.97 mmol/g –1 and a PC value of 2.08 × 10 –2 S/cm –1 at 100 °C. The Arrhenius plot of PC as a function of temperature revealed that the proton transport in the membrane might have been eventuated by both Grotthuss and vehicular mechanisms. The 10% SnO 2 NP-embedded SPTPAES NC membranes also showed excellent oxidative stability with a value of 45.7% degradation after being exposed to a Fenton reagent at 100 °C for 8 h.