Synergistic Combination of Pd and Co Catalyst Nanoparticles over Self-Designed MnO2Structure: Green Synthetic Approach and Unprecedented Electrode Kinetics in Direct Ethanol Fuel Cell

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.