LAUSR

The oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are important electrochemical reactions to realize clean energy technologies. Herein, we prepared a hybrid electrocatalyst consisting of Co/CoOx nanoparticles embedded in amorphous carbon through the simple pyrolysis of cobalt-based zeolitic terephthalate frameworks. The pyrolysis temperature significantly influenced the structure morphology and catalytic behavior. Good contact between Co/CoOx and amorphous carbon resulted in a high catalytic efficiency. The hybrid obtained under pyrolysis temperature of 600 °C exhibited the highest performance for OER, offering a stable current density of 10 mA cm-2 at 277 mV in basic media. Besides good OER behavior, it also showed good ORR performance [onset potential: ∼0.87 V vs. the reversible hydrogen electrode (RHE), diffusion-limiting current density: ∼4.9 mA cm-2 ]. This work describes a novel and efficient catalyst, and greatly expands the scope of low-cost Co-based electrocatalysts for various electrochemical reactions without the need for N-containing ligands.