Green synthesis of CuCo2O4-CuO composite nanoparticles grown on nickel foam for high-performance oxygen evolution reaction

Among the most critical components for water-derived hydrogen fuel, the study of elec-trocatalysts as anode for the oxygen evolution reaction (OER) is an important topic in the water splitting process. In this work, the CuCo2O4-CuO composite electrode is synthesized directly on nickel foam to evaluate its potential as OER catalyst in an alkaline medium. An interesting strategy is to use flaxseed oil as a polymerizing agent in a sol-gel process combined with hydrothermal. A low overpotential value of 289 mV vs RHE at 10 mA cm-2 current density and a Tafel slope of 71 mV dec-1 were observed, which represents an electrocatalytic performance superior to other Cu and Co based oxides in the literature. Short-term stability testing of 15 h demonstrates stable overpotential with no observable secondary phase after measurements. The successful outcome of this work is a result of the promising green chemical approach herein used to obtain electrocatalysts grown directly on conductive substrates for water oxidation.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, a copper cobalt oxide-copper oxide composite electrode was synthesized using flaxseed oil as a polymerizing agent in a sol-gel process combined with hydrothermal method. The composite electrode showed a low overpotential and superior electrocatalytic performance compared to other copper and cobalt based oxides. Short-term stability testing also demonstrated good stability with no observable secondary phase.