Regulating Lattice Oxygen of Co3O4/CeO2 Heterojunction Nanonetworks for Enhanced Oxygen Evolution

Developing efficient and cost‐effective electrocatalysts as substitutes for noble metals remains a big challenge, which demands significant advancements in both material designing and mechanistic understanding. Herein, Co3O4/CeO2 heterojunction nanonetworks are successfully synthesized through metal organic framework precursor. Notably, Co3O4/CeO2 heterojunctions can effectively regulate electronic structure of Co3O4, thus inducing oxygen atom from Co3O4 lattice to participating in oxygen evolution reaction (OER) via lattice oxygen‐mediated mechanism, which reduces reaction overpotential. Additionally, the porous network structure can facilitate electrolyte transfer and provide more active sites for electrocatalytic reactions. Consequently, Co3O4/CeO2 heterojunction nanonetworks exhibit great electrocatalytic performance and high durability, requiring only an OER overpotential of 259 mV at current density of 100 mA cm−2 in 1 M KOH, markedly outperforming Co3O4 nanocatalysts (309 mV) and showing promising potential as substitutable non‐noble OER catalysts. Co3O4/CeO2 nanocatalysts show great oxygen evolution reaction (OER) activity owing to the porous network that favors mass transfer and the heterojunctions regulate electronic structure of Co3O4 that induces oxygen atoms from Co3O4 lattice to participate in OER, thereby resulting in its accelerated electron transfer and enhanced intrinsic catalytic activity.