Remarkable performance of the unique Pd–Fe2O3 catalyst towards EOR and ORR: non-Pt and non-carbon electrode materials for low-temperature fuel cells

Abstract

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.