Electrocatalytic oxygen evolution of ultrafine nano-Co3O4 coupled with N-rich carbon composites

Abstract

Transition metal oxide is a kind of catalyst with high catalytic activity for electrocatalytic oxygen evolution reaction. However, the catalytic activity is limited by the low electronic conductivity. The effective way to construct high performance electrode material or electrochemical catalyst is combining the nano material with conductive matrix material. The polymerized porphyrins supported on C3N4 were prepared by solvothermal method. The Co3O4/NC catalyst was prepared by Co modification and heat treatment of BDA-PY/C3N4. The physicochemical properties of the catalyst were characterized by XRD, SEM, TEM, XPS and FT-IR, and so on. The results indicate that Co3O4/NC-600 possesses a super-small nano-Co3O4 structure and high nitrogen content. The strong chemical bond between pyridinic N of the nitrogen-doped carbon and Co is formed, resulting in a synergistic effect, which makes the catalyst show good catalytic performance in OER reaction. Its Tafel slope is only 66.4 mV/dec and the minimum overpotential is 343.3 mV when the current density reaches 10 mA/cm2.