Fabrication of multifaceted palladium nanoparticles supported on nitrogen-doped carbon dots for enhanced oxygen reduction and magnetic field response studies

This study introduces a novel electrode material composed of nitrogen-doped carbon quantum dots (N-CQDs) decorated with palladium nanoparticles. The N-CQDs were synthesized using a pyrolysis like method involving glucose and urea and characterized using various techniques, including TEM, FTIR, Raman, SEM, EDS, XPS and XRD. The nitrogen content of the N-CQDs was found to be 20 % by elemental analysis. Multifaceted palladium nanoparticles were subsequently anchored onto the N-CQDs and utilized as a catalyst for enhanced oxygen reduction reaction (ORR) in an alkaline medium. A magneto-electrochemical system was established to comprehensively investigate the influence of magnetic fields on the electrocatalytic process. The results demonstrate that the electron transfer number remains relatively constant at approximately 4 for both magnetized and non-magnetized Pd/N-rCQDs while the tafel slope exchange from 36 mV/dec to 40 mV/dec. However, the application of a magnetic field significantly improves the performance in both the mixed and diffusion regions of the ORR, with an enhancement of approximately 100 %. These findings highlight the potential of nitrogen-doped carbon quantum dots, metal nanoparticles and the synergistic effects of magnetic fields in optimizing electrocatalytic reactions.