Electrochemical behavior of Pt nano-particles dispersed on Cu/Ni electrode in alkaline environment

Abstract

The development of a low-cost Pt-based electrocatalyst for industrial water splitting is important. In this study, to prepare cost-efficient Pt-based electrocatalyst for hydrogen evolution, Cu electrode is deposited with nickel (Cu/Ni) and this surface is modified with Pt nanoparticles by electrodeposition method (Cu/Ni–Pt). The surface properties of the produced electrocatalysts are studied via X-ray diffraction (XRD), scanning electron spectroscopy (SEM), energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Characterizations demonstrated that the coating is homogeneous and compact. Hydrogen evolution and corrosion behaviors of prepared electrode (Cu/Ni–Pt) are examined in 1.0 M KOH solution using cyclic voltammetry (CV) and cathodic and anodic current-potential curves, electrochemical impedance spectroscopy (EIS). Tafel slope is determined to be 133 mV dec−1 on Cu/Ni–Pt. Very high exchange current density (5.65 mA cm−2) and very low charge transfer resistance (0.91 Ω cm2 at 1.05 V vs RHE) are measured again on this electrocatalyst. High activity is due to intrinsic activity of Pt and synergistic interaction of Pt and Ni. Besides, Cu/Ni–Pt exhibits so stable structure over 4 h without any current densities decay as well as showing good corrosion performance after long-term immersion times and these properties make it possible electrocatalyst with high corrosion resistant and activity in the water electrolysis systems.