MOF‐Derived Hollow CoS Decorated with CeO x Nanoparticles for Boosting Oxygen Evolution Reaction Electrocatalysis

Abstract Transition‐metal sulfides (TMSs) have emerged as important candidates for oxygen evolution reaction (OER) electrocatalysts. Now a hybrid nanostructure has been decorated with CeO x nanoparticles on the surface of ZIF‐67‐derived hollow CoS through in situ generation. Proper control of the amount of CeO x on the surface of CoS can achieve precise tuning of Co 2+ /Co 3+ ratio, especially for the induced defects, further boosting the OER activity. Meanwhile, the formation of protective CeO x thin layer effectively inhibits the corrosion by losing cobalt ion species from the active surface into the solution. It is thus a rare example of a hybrid hetero‐structural electrocatalyst with CeO x NPs to improve the performance of the hollow TMS nanocage.