Preparation of NiPCeO2 electrode and study on electrocatalytic properties for hydrogen evolution reaction

In this study ternary NiPCeO2 catalysts were first synthesized by the Coelectrodeposition 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 NiCeO2, NiP, 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 Xray spectrometry (EDX) and Xray diffraction (XRD) methods. The electrochemical efficiency of all investigated catalysts was studied based on electrochemical data obtained from electrochemical impedance spectroscopy (EIS) and steadystate polarization Tafel curves in 1 M NaOH solution. The results showed that microstructural properties play an essential role in the high electrocatalytic activity of NiPCeO2. Furthermore, it was observed that the HER mechanism for all investigated systems was VolmerHeyrovsky with a Volmer step as the rate determining step (RDS). The NiPCeO2 catalyst, as the most active catalyst in this work, was characterized by an exchange current density of j0=168.0 µAcm2, a Tafel slope of b=162.0 mV.dec1, and overpotential at j0=250 mAcm2; η250=143.0 mV.