Efficient fish-scale CeO2/NiFeCo composite material as electrocatalyst for oxygen evolution reaction.

An electrochemical catalyst with efficient, stable, inexpensive energy storage for oxygen evolution and hydrogen evolution has raised global concerns on energy, calling for high-performance materials for effective treatments. In this paper, novel amorphous polymetallic doped CeO2particles were prepared for an electrochemical catalyst via homogeneous phase precipitation at room temperature. Metal ions can be easily embedded into the oxygen vacancies formed by CeO2, and the the electron transport capacity of the CeO2/NiFeCo electrocatalyst is improved owing to the increase in active sites. In addition, the amorphous CeO2/NiFeCo composite material is in a metastable state and will transform into different active states in a reducing or oxidizing environment. Furthermore, the amorphous material drives oxygen evolution reaction (OER) through the lattice oxygen oxidation mechanism (LOM), while LOM can effectively bypass the adsorption of strongly related intermediates in the adsorbate release mechanism, thus promoting OER procedure in a timely manner. As a result, CeO2/NiFeCo exhibits a lower oxygen evolution overpotential of 260 mV at 10 mA cm-2current density, which shows a predatorily competitive advantage compared with commercially available RuO2and the reported catalysts.