3D flower-like polypyrrole-derived N-doped porous carbon coupled cobalt oxide as efficient oxygen evolution electrocatalyst

Abstract

For electrochemical splitting of water, highly active and non-precious metal electrocatalysts towards the oxygen evolution reaction (OER) are direly needed to address the cost and stability issues. Herein, polypyrrole (PPy) with 3D flower-like structure has been prepared to obtain N-doped porous carbon sheets (N–C) and to implant with cobalt oxides (Co3O4) via simple and cost-effective hydrothermal reaction. Benefitting from the 3D flower-like porous carbon structure, Co3O4/N–C demonstrates enlarged surface area replenished with more electrocatalytic active sites. What's more, Co3O4 nanoparticles are evenly dispersed onto the N-doped carbon surface which effectively prevents their aggregation and detachment. These exclusive structural features render amazing catalytic activity for Co3O4/N–C towards OER with an onset potential of ~1.31 V (vs RHE), low overpotential of 120 mV at 10 mA cm−2 and a Tafel slope of only 33 mV dec−1 in basic media. This work presents a simple approach to meet an ideal catalytic material with better morphology and advantageous properties for the possible energy and environmental applications.