Single-Step Electrochemical Deposition of Transition Metal-Doped CoNi@Ti Nano-Flowers for Enhanced Oxygen Evolution Reaction

Abstract

Recently, transition metal-based electrocatalysts have shown significant promise in promoting the oxygen evolution reaction (OER) as a result of their ample availability, tunable electronic properties, and catalytic capabilities. This study presents the synthesis of a transition metal-based electrocatalyst, featuring Co and Ni nanoparticles grown on Ti foil (CoNi@Ti). These nanoparticles are doped with Mn and Fe using with single-step in-situ chronoamperometry (CA) electrodeposition technique, resulting in the production of the Fe-MnCoNi@Ti nano-flower material. The results show that the Fe-MnCoNi@Ti nano-flower, with an overpotential of 261.6 mV, is an efficient electrocatalytic system for OER, achieving 10 mA cm⁻² and a Tafel slope of 114.3 mV dec⁻¹ in alkaline media. The comparison of the electrocatalytic performance of Fe-MnCoNi@Ti with other materials prepared in the same electrodeposition techniques and with the state-of-the-art materials indicated that our nano-flower material has comparable performance on its electrocatalytic properties for OER. In addition, the Turnover frequency (TOF) value highlights the high intrinsic activity of Fe-MnCoNi@Ti in catalyzing the OER. The stability test is also carried out by applying an overpotential of 400 mV with respect to the OER for 12 h of CA run, and it is found that Fe-MnCoNi@Ti has good stability for OER in alkaline conditions. The experimental results indicate that decorating Coniston nano-flower with Fe and Mn as dopant materials via electrodeposition technique is a simple one-step process, which led to better electrocatalytic performance of the material for the OER in alkaline media.

Graphical Abstract