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In this investigation the effect of temperature on catalytic oxidation of ethanol on multi‐metallic PdCoNi/C nano‐composite bearing reduced palladium loading, have been studied over the temperature range 20 °C to 80 °C. The structure, composition and surface morphology of the catalyst regime were determined through the respective techniques like XRD, EDX and TEM while electro‐catalytic parameters were evaluated by the help of voltammetry, chronoamperometry, impedance spectroscopy and ion‐chromatography. The apparent activation energies (Ea) of ethanol oxidation reaction (EOR) were drastically reduced over PdCoNi/C compared to Pd/C reflecting the energy efficiency of ternary matrix furnished with only 35 % Pd loading and the rest 65 % being cheaper transition metals. The long term poisoning rates warrant improved stability of PdCoNi/C and also figure out the robustness of the catalyst even at 20 °C. The Ea value is remarkably reduced, rendering appreciable mass activity in terms of current density per mg of Pd at each of the temperatures studied. The incorporation of transition metals Co and Ni onto Pd becomes particularly effective in orienting the EOR proceed through carbonate pathway as reflected by the columbic efficiency in terms of oxidation product yield ~5 times higher, compared to single Pd catalyst throughout the temperature range. [ABSTRACT FROM AUTHOR]

The present investigation deals with Pd NPs casted over Fe2O3 support in formulating Pd/Fe2O3 catalyst with a complete non-Pt and non-carbon approach toward accomplishing the electrocatalysis of ethanol oxidation reaction (EOR) at the anode and oxygen reduction reaction (ORR) at the cathode in alkaline media for low-temperature fuel cell. The high electrochemical surface area (ECSA) for Pd/Fe2O3 with smart intervention of Fe2O3 directly/indirectly in EOR and ORR sequences makes this distinct catalyst a highly preferred choice in direct ethanol fuel cell with respect to reduced polarization loss, substantial current density output, and greater stability compared to the usual Pt or Pd nano-catalysts supported over carbon. Studies involved morphology, which was determined through electron microscopy and electrochemical characterization with the help of potentiodynamic polarization and RDE-RRDE techniques. The catalytic pre-eminence of the nanostructured Pd/Fe2O3 was manifested by the facile electrode kinetics at the anode and the cathode, low yield of H2O2 in ORR, and appreciable power density output of 36.01 mW cm−2 of the complete cell bearing enormous mass activity for both EOR and ORR. This novel attempt of introducing the same robust catalyst at both ends ensures better catalyst utilization, imparts affordability, and avoids carbon corrosion in the fuel cell environment. [ABSTRACT FROM AUTHOR]