Electrodeposited Ni-Se on recycled steel substrate as eco-friendly electrodes with enhanced electrocatalytic activity towards urea oxidation reaction

Minimizing e-waste by extracting valuable parts or by utilizing them for the development of devices can be a productive way to manage it. The present research work focusses on the use of electrochemically modified steel mesh (SM) extracted from discarded nickel-metal hydride (Ni-MH) batteries for the application of energy generation. Upon deposition of amorphous nickel selenide film on SM, significant activity towards catalysing the urea oxidation reaction (UOR) is reported. Electrodeposition of Nickel selenide on SM was confirmed by analytical techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), and EDX studies. Electrochemical studies reveal that for NiSe@SM a potential of 1.375 V vs RHE is needed to obtain a current density of 10 mA cm⁻², which is significantly higher than the noble metal-based mixed metal oxide (MMO) catalyst. Further, the NiSe@SM showed minimum Tafel slope of 47 mV dec⁻¹ and exhibited minimum charge transfer resistance among all the tested films. Furthermore, the film showed stability of 9 h confirming the robustness of catalyst. The findings indicate that the inclusion of Selenium led to an improvement in the activity and kinetics of the UOR. This research lays the groundwork for developing environmentally acceptable electrode materials from electronic waste for generating sustainable energy.