Boosting oxygen evolution reaction of NiCo2O3 Nanoflowers by Se incorporation

Developing non-noble transition metal electrocatalysts with high catalytic activity and durability is essential for the oxygen evolution reaction (OER). Herein, novel nanoflower-like Se-NiCo2O3 electrocatalyst (Se-NiCo2O3 NFs) were fabricated via a hydrothermal refluxing and high-temperature calcination strategy. The electrochemical test results demonstrated that the 7 wt% Se-NiCo2O3 NFs exhibit superior OER activity compared with the pristine NiCo2O3 NFs, requiring an overpotential of 290 mV to reach a current density of 10 mA cm-2 along with a low Tafel slope of 56.89 mV dec-1. Their superior and stable catalytic performance can be attributed to structure advantage and Se doping. The nanoflower structure provides a large specific surface area to expose abundant active sites. In addition, the doping of Se can further increase the electrical conductivity and regulate the electronic structure of metal atoms, promoting the adsorption of reaction intermediates such as OH* and enhancing the material's oxygen evolution capability. This work provides new insights and methodologies for designing efficient and stable Se-doped metal oxide electrocatalysts.