Monolayer High-Entropy Layered Hydroxide Frame for Efficient Oxygen Evolution Reaction.

High-entropy materials with tailored geometric and elemental composition provide a guideline for designing advanced electrocatalysts. Layered double hydroxides (LDHs) is a most efficient oxygen evolution reaction (OER) catalyst. However, due to the huge difference in ionic solubility product, an extremely strong alkali environment is necessary to prepare high-entropy layered hydroxides (HELHs), which results in the uncontrollable structure, poor stability and scarce active sites. Here, we present a universal synthesis of monolayer HELH frame in a mild environment, regardless of the solubility product limit. Mild reaction conditions allow us to precisely control the fine structure and elemental composition of the final product. Consequently, the surface area of the HELHs is up to 380.5 m g . The current density of 100 mA cm is achieved in 1 M KOH at an overpotential of 259 mV. And after 1000 hours operation at the current density of 20 mA cm , the catalytic performance shows no obvious deterioration. The high-entropy engineering and fine nanostructure control open opportunities to solve the problems of low intrinsic activity, very few active sites, instability, low conductance during OER for LDH catalysts. This article is protected by copyright. All rights reserved.