Journal of Materials Research and Technology (Mar 2021)
Aid of cobalt ions in boosting the electrocatalytic oxygen and hydrogen evolution functions of NdFeO3 perovskite nanostructures
Abstract
Inorganic perovskite nanostructures based on neodymium (Nd) were processed in form of nanostructures for bi-functional electrocatalytic reactions. The active role of Co ions in influencing the material characteristics of Nd-ferrite (NdFeO3) were investigated in detail. The nanostructural characteristics were adjudged through the aid of diffraction and high-resolution microscopic studies. Evidences relating to the co-occurrence of neodymium oxides (Nd2O3) were also noticed. The valency of Nd, Co and Fe ions and their nature of interaction in the ferrite architecture was studied through X-ray photoelectron spectroscopy. Here, convincing affirmations relating to the partial substitution of Co ions in place of Nd and Fe sites were also made. NdFeO3 and NdxCo1-xFeO3 nanostructures were studied for their electrocatalytic functions under varied alkaline pH (10 and 14) conditions. The improved conductivity studied via electrochemical impedance analysis in Co incorporated ferrites were noted to accelerate oxygen/hydrogen production in the corresponding electrodes. The overpotential values corresponding to oxygen evolution reactions reduced to 198 mV from 227 mV, while hydrogen evolution reactions lowered to 206 mV from 239 mV upon Co substitution. Similarly, the related Tafel slope values got improved in Co substituted ferrite matrix. The overall stability related electrochemical data suggested the processed ferrites as viable bi-functional electrocatalysts possessing essential features required for effective oxygen and hydrogen evolution reactions.