In-situ self-catalytically grown CoNi-doped C-N/CNT as a binder-free electrocatalyst for high-performance oxygen evolution reaction

Abstract

In this study, an efficient electrocatalyst for the oxygen evolution reaction (OER) was developed by in-situ self-catalytic growth of CoNi-doped carbon nanotubes (CNTs). The synthesized electrocatalyst had well-defined dimensions with CNTs measuring 200 nm in diameter and 2 µm in length. The optimal CoNi@CNT/NM-3 sample exhibited remarkable OER performance with a low overpotential of 265 mV at a current density of 50 mA cm−2 and a Tafel slope of 97.3 mV dec−1. Further, the prepared CoNi@CNT/NM-3 electrocatalyst also demonstrated long-term stability over a 100 h period. These enhanced electrochemical properties can be attributed to the unique three-dimensional network structure of the catalyst, the large diameter of the carbon nanotubes facilitating efficient conductivity, and the presence of exposed active sites on the catalyst surface.