Boosting the charge transfer of FeOOH/Ni(OH)2 for excellent oxygen evolution reaction via Cr modification

Abstract

For the electrocatalytic oxygen evolution reaction (OER) in alkaline media, there is an urgent need to optimize the adsorption strength of OH*. Here, a flower-like hybrid of Cr-doped FeOOH/Ni(OH)₂ was used as an OER catalyst with a low overpotential of 291 mV at 50 mA cm⁻². The results showed that faster charge transfer was achieved at the electrode/solution interface during the OER process after the FeOOH/Ni(OH)₂ was modified by Cr, which facilitates the rate-determining step of the Volmer reaction. Furthermore, the results of faradaic efficiency and X-ray photoelectron spectroscopy (XPS) measurements confirmed that the synergistic effect between the ternary metal and oxygen vacancies led to excellent OER performance. This work provides a new strategy for the preparation of high-efficiency and low-cost oxygen evolution electrocatalysts.