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Herein, we report the design and fabrication of highly efficient self-humidified electrocatalyst for the enhancement of polymer electrolyte fuel cell (PEFC) performance. An optimum level of silica decorated carbon as an alternative and ultra-stable support to platinum catalyst is prepared by a versatile one-pot synthesis method. The surface morphology, crystallinity, chemical oxidation states and metal/metal oxide-carbon interfacial distribution are examined by High resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, respectively. An optimum level of silica decorated carbon supported Pt (Pt/SDC) boosts the performance and stability of PEFC even up to 200 h in relation to Pt/C under dry gas condition. In addition, the effect of temperature and relative humidity on both anode and cathode is investigated by steady-state cell polarization. A 15-cell air-cooled indigenous prototype PEFC stack is designed, fabricated and assembled. An optimum level of silica decorated on carbon supported Pt employed 15 cell air-cooled stack shows superior power of 104 W at 8 V and also retains more than 96% of initial performance even after 200 h of steady-state operation. In the present work, an optimum level of silica retain water in the triple phase boundary in individual cells, which in turn enhances the overall stack performance and stability even after 200 h of steady-state operation under dry gas feed.

Optimum amount of carbon semi-coated on titania nanorods-Pt (Pt/CCT) electrocatalyst increases the cell performance and long term durability in low-temperature polymer electrolyte fuel cells (LT-PEFC). Semi-coated carbon on titania nanorods support (CCT) is synthesised hydrothermally followed by Pt deposited using polyol method. A thin metal loading of 150 μg cm−2 with an active area of 50 cm2 exhibits a high current of 49 ± 0.5 A at 0.6 V for 100 h without back pressure in H2:O2 configuration. In the present study, 5 and 15 cell LT-PEFC stacks and their engineering aspects towards development of indigenous cell fixture and assembly are explored in detail. The 5 cell stack durability at 5 A for 125 h shows a minimal voltage loss of 4 μV h−1. In addition, 15 cell air cooled prototype indigenous fuel cell fixture is fabricated and demonstrated with electrical power of 310 W at 9 V. In a single cell, Pt/CCT retains 85% of initial current at 0.6 V during start-stop cycles (100 h) in H2:air configuration as compared to Pt/C.

Stable hybrid support for platinum is prepared for polymer electrolyte fuel cells (PEFCs). The synergetic interaction between platinum and optimum level of iron and nitrogen co-doped into titania (TiON Fe) framework moiety leads to superior cell performance and long-term stability as compared to platinum on carbon. Pt metal nanoparticles are deposited on TiON Fe framework by colloidal method. Accelerated durability test (ADT) are performed for both Pt/C and Pt/TiON Fe framework by potential hold at 1.2 V. The corrosion stability is increased for platinum deposited on TiON Fe framework in PEFC and retains 50% of cell performance even after 200 h as compared to Pt/C with only 18% of cell performance for 80 h. The degradation of catalyst and loss of cell performance are explained by various characterizations before and after ADT.