preparation of ni-p-ceo2 electrode and study on electrocatalytic properties for hydrogen evolution reaction

In this study ternary ni-p-ceo2 catalysts were first synthesized by the co-electrodeposition method on a copper substrate and then characterized by means of microstructural and electrochemical techniques toward a hydrogen evolution reaction (her). also, for comparison other catalysts such as ni-ceo2, ni-p, and ni were prepared and characterized by the same methods. the microstructure of the investigated catalysts was characterized by scanning electron microscopy (sem) coupled with energy dispersive x-ray spectrometry (edx) and x-ray diffraction (xrd) methods. the electrochemical efficiency of all investigated catalysts was studied based on electrochemical data obtained from electrochemical impedance spectroscopy (eis) and steady-state polarization tafel curves in 1 m naoh solution. the results showed that microstructural properties play an essential role in the high electrocatalytic activity of ni-p-ceo2. furthermore, it was observed that the her mechanism for all investigated systems was volmer-heyrovsky with a volmer step as the rate determining step (rds). the ni-p-ceo2 catalyst, as the most active catalyst in this work, was characterized by an exchange current density of j0=168.0 µacm^-2, a tafel slope of b=-162.0 mv.dec^-1, and overpotential at j0=250 macm-2; η250=-143.0 mv.