High-performance oxygen evolution reaction activity at low and higher current densities using nanostructured CeO2 and Plasma-assisted Bi@CeO2 electrocatalysts

•Simple and non-alkali reagent hydrothermal synthesis of nanostructured CeO2 (HC)•Plasma engraving to prepare rich-oxygen vacancies electrode of Bi@CeO2 (PBC)•At 10 mA cm−2, the HC electrode displays a low overpotential of 0.32 V, Excellent stability of 99.6 % for 15 h.•The PBC electrode exhibits a low overpotential of 0.46 V at a current density of 250 mA cm−2.•Excellent stability of 99 % for 15 h at a current density of 100 mA cm−2.