Comments on “A facile two-step synthesis of Ag/CuCo2O4 supported on nickel foam as a high-performance electrocatalyst for oxygen evolution reaction. Materials Letters 275 (2020) 128094.”

Abstract This is a comment on the paper Materials Letters 275 (2020) 128,094 (DOI: https://doi.org//10.1016/j.matlet.2020.128094) titled “A facile two-step synthesis of Ag/CuCo2O4 supported on nickel foam as a high-performance electrocatalyst for oxygen evolution reaction”. Herein, we conducted a critical assessment on interpretation of the experimental results, revealing that the reported overpotentials of only 36 and 68 mV vs. RHE for a current density of 20 mA cm−2 toward OER are mistaken.