Pd/fMC-NiO Synergistic, Promotional Effect and Cooperation Induced Electrocatalysis towards Ethylene Glycol Electrooxidation: Experimental Approach and DFT Calculations

Direct alcohol fuel cells (DAFCs) face several challenges such as carbon support corrosion, poor kinetics, and long-term stability, requiring improved electrocatalyst support development. We synthesized 5 %Pd/fMC-NiO using a microwave-assisted sodium borohydride-enhanced polyol method. X-ray photoelectron spectroscopy, transmission electron microscope, and X-ray diffractometry probed the material's surface composition, morphology, and structure. ICP-OES is employed to quantify palladium loading. Fourier Transform Infrared Spectroscopy mapped the functional groups. Cyclic voltammetry, linear sweep voltammetry, electrochemical impedance spectroscopy, and chronoamperometry show that the 5 %Pd/fMC-NiO has the lowest activation energy, and with that, the best electroactivity, which is similar to 16 times higher compared to commercial Pd/C; additionally, the catalyst shows anti-poisoning properties, and long-term durability. This is merited to the cooperation and promotional effect of Pd/fMC-NiO. The electrocatalysts' electroactivity improved via enhanced electron movement instigated by NiO. This study introduced the parallelism effect concept borrowed from the graphite structure for controlled electron channeling the 5 % Pd/fMC-NiO electrocatalyst. The theoretical calculations corroborated the experimental findings that our approach favors anchoring and dispersing Pd NPs uniformly, demonstrating NiO ' s cooperative and promotional effects. Thus, opening new opportunities for the development of electrocatalysts for high-performance DAFCs.