CoP/CoN heterostructural active centers supported on nitrogen carbon nanorod arrays as freestanding high-performance trifunctional electrocatalysts

Abstract

Developing high-activity and long-term durable trifunctional electrocatalysts for the oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is of crucial significance and demanding. In this work, a CoP/CoN heterostructural active center supported by nitrogen carbon nanorod arrays on carbon cloth catalyst (CoP/CoN@NCNRs/CC) is reported and acts as a self-supported electrode for zinc–air batteries and water splitting. Both density functional theory calculation (DFT) and experimental results reveal that the favourable catalytic performance is due to the highly dispersed active sites where Co–N_x–C with ORR and OER activity and CoP with OER and HER activity exhibited a synergistic role. Furthermore, the NCNRs can protect the active sites from corrosion and participate in the ORR. CoP/CoN@NCNRs/CC as an air electrode for liquid zinc–air batteries possesses a great power density and energy density and shows superior stability with a long operating life of more than 420 h at 10 mA cm⁻². The all-solid-state Zn–air batteries and water splitting device are self-assembled and both of them have potential for application in flexible electronics and new energy devices.