MOF‐Derived Hollow CoS Decorated with CeO_<i>x</i> Nanoparticles for Boosting Oxygen Evolution Reaction Electrocatalysis

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 Co²⁺ /Co³⁺ 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.