Electrocatalysis property of CuZn electrode with Pt and Ru decoration

Abstract

Electrocatalysis properties strongly depend on the interaction of metallic particles and this interaction enables to change the electronic structure of alloys which enhances the catalytic activity. This property is the key factor in the developing of cost-effective and efficient Hydrogen Evolution Reaction (HER) electrocatalysts for sustainable hydrogen production. In this study, novel electrocatalysts which are decorated with Pt and Ru have been developed for HER electrocatalysis. Microscopic analysis such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM) are performed to determine the morphological and compositional structures. Electrocatalysis properties are evaluated by cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1.0 M KOH solution. Chronoamperometry (CA) and cycle tests are used for stability/durability of electrocatalysts. Results show that a small onset potential of the porous Cu/Ni/CuZn–Pt is obtained for HER. Exchange current density and polarization resistance are found to be 5.39 mA cm−2 and 2.0 Ω cm2 at overpotential of −100 mV for porous Cu/Ni/CuZn–Pt, respectively, indicating that Cu/Ni/CuZn–Pt is higher electrocatalytic properties than the others. Moreover, very low overpotentials at 10 and 40 mA cm−2 are obtained on porous Cu/Ni/CuZn–Pt compared with porous Cu/Ni/CuZn–Ru and Cu/Ni/CuZn. Porous Cu/Ni/CuZn–Pt also displays excellent stability/durability in test solution. The remarkable electrocatalysis properties of porous Cu/Ni/CuZn–Pt can be explained due to high porous structure, leaching of Zn from the deposit, intrinsic activity of Pt as well as changing in the electronic structure. It should be considered that porous Cu/Ni/CuZn–Pt is of high corrosion resistance in test solution for 120 h, which makes it good candidate for HER.