A novel titanium-supported nickel electrocatalyst for cyclohexanol oxidation in alkaline solutions

A novel titanium-supported nickel electrode (Ni/Ti) is fabricated by a simple hydrothermal process using hydrazine hydrate as a reduction agent. Its electrocatalytic activity towards cyclohexanol oxidation has been investigated by cyclic voltammetry (CV), chronoamperometry (CA), quasi-steady state polarization and electrochemical impedance spectroscopy (EIS). Effects of various parameters such as potential scan rate and cyclohexanol concentration on the electro-oxidation of cyclohexanol are investigated. Results show that the Ni/Ti electrode behaves as an efficient catalyst for the electro-oxidation of cyclohexanol in basic media and its electrocatalytic activity towards cyclohexanol oxidation is higher than a nickel oxyhydroxide modified nickel electrode (NOMN). It is confirmed that during the anodic potential sweep the electro-oxidation of cyclohexanol follows the formation of NiOOH on the electrode surface and is then catalysed by NiOOH. The rate-determining step for cyclohexanol oxidation is the reaction between the high oxidation state nickel (Ni3+) and the adsorbed cyclohexanol on the surface of the Ni/Ti.