LAUSR

ABSTRACT In this paper, the effects of coordination ions, which were synthesized using NH3•H2O, on the morphology and electrocatalytic properties of the materials were investigated in a solvothermal reaction. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the structure and composition of the synthesized material. The N2 adsorption/desorption measurements showed that the material had a large specific surface area (135.051 m2/g), indicating that it was a mesoporous material. X-ray photoelectron spectroscopy (XPS) was used to analyze the orbital and valence distribution of atoms and the number of oxygen vacancies in the materials, and to explore the effect of oxygen vacancies on the electrocatalytic performance. The mobility of oxygen elements in the catalysts was further analyzed using the oxygen programmed temperature desorption (O2-TPD) technique. The materials were tested using cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The results showed that the current density of NiCo2O4 synthesized with the help of NH3•H2O was 132.4 mA/cm2 at 0.6 V potential in the electrolyte of 1 M KOH+0.5 M CH3OH. Under the same conditions, NiCo2O4 without NH3•H2O-assisted synthesis had a current density of 68.5 mA/cm2, and the material showed good stability. After 500 cycles, the synthesized material attenuated to 8%, which showed good potential for practical applications and further development.