Kinetic properties of the Ti-Ni intermetallic phases and alloys for hydrogen evolution

Abstract

The kinetics and mechanism of hydrogen evolution at Ti-Ni alloy electrodes prepared by are-melting and mechanical alloying methods has been studied by means of AC impedance spectrum measurements. The electrode, prepared by mechanical alloying (porous electrode), after activation in a 10% HF solution, is very active despite its large Tafel slope. The SEM studies show a formation of deep pores on the electrode surface. The rate constants of the forward and backward reactions of the corresponding steps were estimated by a nonlinear fitting method. It has been found that the overall reaction proceeds through a Volmer-Heyrovsky mechanism.