Pd2CuCo/C Hybrid with Nanoflower Morphology toward Oxygen Reduction and Formic Acid Oxidation Reactions: Experimental and Computational Studies

A unique and novel structural morphology with advantageous surface defects, lattice strain, and a preferentially exposed crystal plane are indispensable criteria for offering superior and durable electrocatalytic performance. However, the design of a single electrocatalyst (EC) with all such splendors is still a challenging task. Here, we successfully developed a one pot, surfactant and organic structure directing agent free alternative EC based on Pd2CuCo/C hybrid with nanoflower (NF) morphology. The efficacy of electrode is offered by highly open hierarchical nanostructures with a preferentially exposed (111) plane and multiple surface defects. Moreover, the half implanted Pd2CuCo on a carbon matrix offers high stability and the metal/carbon interface provides faster electron transfer during the fuel cell operation process. Remarkably, Pd2CuCo/C NF shows significant electrocatalytic activity toward the oxygen reduction reaction (ORR). A current density of 5.5 mA cm–2, an onset potential of −0.018 V (vs Ag/AgCl), and a half-wave potential of −0.138 V were noted for the ORR of Pd2CuCo/C NF. It delivered good methanol tolerance and enhanced stability with ∼80.3% of the retention current, even after 21,600 sec at 1600 rpm, unlike the benchmark Pt/C catalyst. Moreover, computational studies show that Co and Cu doping in Pd2CuCo/C alloy NF will inhibit the degradation of the electrocatalytic activity caused by strong CO adsorptions. The greater accessible active sites, the strong interfacial interaction between Pd2CuCo NF and the carbon matrix, and the excellent synergistic interaction between Pd and Cu, Co are the major marvels for such superior electrocatalytic performance. Therefore, the present investigation offers a promising approach of designing high-performance non-Pt ECs.