Synthesis of PdCu supported by carbon and carbon hybrid tungsten oxides (C-WO3) nanoparticles and its effect on oxygen reduction reaction (ORR) in acidic and alkaline media: density functional theory approach

In this study, palladium and copper alloy supported on carbon and carbon hybrid tungsten oxide (IV) (WO3) for the oxygen reduction reaction (ORR) catalytic activities have been investigated. The nanostructured PdCu/C catalyst worked effectively in both acidic and alkaline conditions. The impact of adopting a WO3 hybrid support medium i.e., PdCu/C-WO3 on oxygen reduction reaction (ORR) have counted in both media. The phase transfer approach was used to synthesize a stable PdCu nanocatalyst (50:50). The synthesized nanocatalyst were characterized by X-ray diffraction (XRD), high-resolution electron microscopy (HRTEM) and fourier transform infrared (FTIR) techniques. The XRD peaks confirmed the alloy between Pd and Cu, and the particle size was less than 5 nm according to HRTEM. The FTIR data, revealed the bands of oxide's resonance in its distinctive region. The electrochemical behaviour was determined by cyclic voltammetry (CV) via rotating ring disk electrode (RRDE). The WO3 hybrid carbon supported PdCu demonstrated better ORR specificity and mass activities than unhybrid PdCu, in both media. The PdCu/C-WO3 was more efficient than PdCu/C due to the structural effect significantly improved the efficiency of the synthesized nanocatalyst. Density function theory (DFT) calculations corelated with catalytic performance in term of energy of interaction of O2 molecule on the prepared materials as well as its structures orientation and charge transfer approach. Both experimental and the theoretical analysis shows that the PdCu support on carbon hybrid with WO3 have enhanced the catalytic activities for ORR.