Hollow Carbon@NiCo₂O₄ Core–Shell Microspheres for Efficient Electrocatalytic Oxygen Evolution

Abstract

Earth‐abundant transition metal oxides are considered one of the most promising oxygen evolution reaction (OER) catalysts. However, their intrinsically low electrical conductivity inhibits the fast kinetics for OER. To overcome this drawback, hollow carbon@NiCo2O4 core–shell microspheres (C@NiCo2O4 HSs) are synthesized with enhanced electrocatalytic activity and stability toward OER. The prepared C@NiCo2O4/Ni foam delivers a current density of 10 mA cm−2 at a small overpotential of 268 mV and exhibits a low Tafel slope of 54 mV dec−1. The enhanced OER performance is attributed to the enlarged specific surface area induced by the combination effect between the 1D nanosheet structure and the 3D hollow microsphere structure, and the improved electrical conductivity is ascribed to the carbon core support.

In Situ Decorating Coordinatively Unsaturated Fe Sites for Boosting Water Oxidation Performance of TiO2 Photoanode

“…Among these catalysts, RuO 2 and IrO 2 as the representative OER catalysts have exhibited the excellent catalytic performance toward water oxidation, but the expensive cost and deficiency greatly limit its widespread application . Therefore, countless efforts have been devoted to fabricate the efficient and alternative OER cocatalysts to improve the PEC water splitting efficiency, such as transition metal oxides, metallic hydroxides, and C‐doped nanomaterials . Among these materials, the hot topic of metallic hydroxides in the field of catalysis has demonstrated that some metal atoms could show excellent OER catalytic activity, which results from the abundant metal sites acted as the active center .…”