Synthesis and electrocatalytic oxygen evolution performances of FeOOH-Ni(OH)₂ composites

FeOOH-Ni(OH)₂ composites were successfully prepared on carbon fiber cloth (CFC) by electrochemical deposition and hydrothermal method. The electrocatalytic oxygen evolution activity of the FeOOH-Ni(OH)₂ composite is significantly improved compared with FeOOH and Ni(OH)₂. The FeOOH-Ni(OH)₂ electrodes require an overpotential as low as 270 mV and the tafel slope to deliver 10 mA·cm⁻² for oxygen evolution reaction (OER) in 1 mol/L KOH. The electrochemical impedance spectroscopy further reveals the favorable kinetic during electrolysis. Moreover, The FeOOH-Ni(OH)₂ composite has excellent stability in the alkaline medium, and its overpotential remains stable during the 24 h test at high current density(50 mA·cm⁻²). The strong electron interaction and synergistic reaction between FeOOH and Ni(OH)₂ are enhanced effectively. The conductivity promotes the charge transfer, and the core-shell structure effectively enhances the electrocatalytic activity area, and further enhances its oxygen evolution properties.