An approach to the effect of hydrogen loading on the anodic behaviour of Ti in NaOH solutions

Abstract

The voltammetric behaviour of titanium electrode in 0.5 M NaOH solution was investigated. The I‐E curves revealed the presence of a well‐defined O2 evolution peak. The peak current density decreases to a great extent by pre‐loading the metal with hydrogen by cathodic polarization, indicating that pre‐loading the metal with hydrogen suppresses the O2 evolution. The oxidation of hydrogen loaded inside the metal was suggested to be responsible for reducing the O2 evolution peak current density during Ti anodization. The charge consumed during the anodic polarization of Ti, below O2 evolution potential, was used to estimate the anodization coefficient and capacitance measurement was conducted for measuring the dielectric constant of the oxide film. Pre‐loading the metal with hydrogen was found to decrease the oxide film formation rate as well as the dielectric constant.