ZIF-67 derived P/Ni/Co/NC nanoparticles as highly efficient electrocatalyst for oxygen reduction reaction (ORR)

Abstract

P/Ni/Co/NC electrocatalyst (NC is the abbreviation of nitrogen-doped graphitic carbon), with polyhedral morphology and porous structure, was successfully synthesized by using ZIF-67 as precursor. The doping of Ni and P elements have great influence on the structure and properties of the catalyst. All of the synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscope (TEM). The ORR activities of all samples was evaluated by linear sweep voltammetry (LSV) and rotating disk electrode (RDE) technology. The results show that the P/Ni/Co/NC has porous structure and excellent ORR properties. The ORR onset potential of P/Ni/Co/NC is 0.872 V, which is higher than Co/NC (0.847 V) and Ni/Co/NC (0.856 V). And its Tafel slope value (64 mV/dec) is smaller than Ni/Co/NC (86 mV/dec) and Co/NC (97 mV/dec). The excellent ORR activities of P/Ni/Co/NC make its potential to be used as electrocatalyst for fuel cell applications.