Rapid cationic defect and anion dual-regulated layered double hydroxides for efficient water oxidation

Abstract

Defect engineering and anionic regulation are effective approaches to improve the intrinsic activity of oxygen evolution reaction (OER) catalysts, particularly for highly efficient and low-cost cobalt-based electrocatalysts. Layered double hydroxides (LDHs) are considered as promising electrocatalysts toward OER. However, their electronic properties and active sites need to be optimized for their large-scale application. Herein, rapidly cationic defect and anion dual-regulated CoAl LDHs (PS-CoAl LDHs) were in situ synthesized in a few minutes via a modified water DBD plasma treatment. Abundant Al³⁺ vacancies and a relatively rough surface for S²⁻ regulation were formed by the etching effect of the plasma. Consequently, the as-obtained PS-LDHs possess improved intrinsic conductivity and an optimal electronic structure. Simultaneously, the synergistic effect of the Al³⁺ vacancies and S²⁻ regulation promote the exposure of active Co sites, resulting in an amorphous and porous surface for improving the OER performance.