Ethanol oxidation reaction has been studied in acidic environment over PtPd nanoparticles (NPs) grown on the molybdenum oxide–polypyrrole composite (MOPC) support. The attempt was focused on using reduced Pt loading on non-carbon support for direct ethanol fuel cell (DEFC) operated with proton exchange membrane (PEM). As revealed in SEM study, a molybdenum oxide network exists in polypyrrole caging and the presence of metal NPs over the composite matrix is confirmed by TEM analysis. Further physicochemical characterizations such as XRD, EDAX, and XPS are followed in order to understand the surface morphology and composition of the hybrid structure. Electrochemical techniques such as voltammetry, choroamperometry, and impedance spectroscopy along with performance testing of an in-house-fabricated fuel cell are carried out to evaluate the catalytic activity of the materials for DEFC. The reaction products are estimated by ion chromatographic analysis. Considering the results obtained from the above characterization procedures, the best catalytic performance is exhibited by the Pt–Pd (1:1) on MOPC support. A clear intervention of the molybdenum oxide network is strongly advocated in the EOR sequence which increases the propensity of the reaction by making the metallites more energy efficient in terms of harnessing sufficient numbers of electrons than with the carbon support.

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The present study deals with sonochemical synthetic approach in fabricating PdCo/MnO 2 catalyst for the study of ethanol oxidation reaction in alkali medium. SEM and TEM images reveal that MnO 2 morphology is changed from nanowire to nanorod during intercalation of Pd, Co NPs in the support materials. Charge transfer across the electrode− electrolyte interface becomes facile due to (2 × 2) pore tunnels of α MnO 2 . Lowering of Pd loading around 40% in the catalyst matrix by Co not only makes the catalyst cheaper but also enhances the ethanol oxidation current by 66.3% compared to Pd/C. Extensive electrolysis on Pd 61 Co 39 /MnO 2 over a considerable span of potential is reflected in the voltammetric features, typically demonstrating the synergistic effect of the Pd−Co ad atoms ingrained on α MnO 2 structure. Chrono-amperometric analysis for an extended period indicates excellent sustainability of Pd 61 Co 39 /MnO 2 in the oxidation environment. The yield of oxidation products on Pd 61 Co 39 /MnO 2 , derived from ion chromatography, further substantiates the considerable extent of the anodic reactions delivering acetate and carbonates, on average, twice that on Pd/MnO 2 and four to five times that on Pd/C. Finally, 43.88 mW cm −2 power density was achieved during performance testing of the DEFC using the binary catalyst formulation on the noncarbon support.

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