The development of efficient and low‐cost oxygen evolution reaction (OER) catalysts is essential for the generation of clean hydrogen energy from water splitting. Herein, a novel hierarchical urchin‐like cobalt‐copper (hydr)oxide in situ grown on copper foam (CoCuOxHy(S)/CF) was synthesized through the electrochemical transformation of cobalt‐copper sulfides (Co9S8‐Cu1.81S) via anodization process. This CoCuOxHy(S)/CF anode exhibited a low overpotential (η) of 274 mV at a current density of 100 mA cm−2 with a robust durability over a period of 40 h when operated at 10 mA cm−2. Further investigations imply that the unique nanowires aggregated urchin‐like structure of CoCuOxHy(S) derived from the in situ anion exchange process could facilitate the exposure of active sites and accelerate electron transfer. More importantly, the incorporation of copper resulted in an electronic delocalization around the cobalt species, which contributed to reach a high‐valent catalytically active cobalt species and further improved the OER performance.

A novel CuPPc nanoflake material, derived from organic polymers, was used as an excellent water oxidation electrocatalyst for the first time.

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.