Hierarchical nanotubes constructed from CoSe2 nanorods with an oxygen-rich surface for an efficient oxygen evolution reaction

Abstract

Exploring low-cost and highly active electrocatalysts for oxygen evolution has become an urgent requirement for energy-related applications. Increasing the number of active sites and optimizing the electronic structure of electrocatalysts are the key to realizing high catalytic activity. Herein, we report a controlled-selenylation self-templating strategy for synthesizing hierarchical structural oxygen-modified nanotubes as an electrocatalyst (O–CoSe₂-HNT). The hierarchical structural O–CoSe₂-HNT catalyst with an oxygen-rich surface exhibits an excellent catalytic activity for the oxygen evolution reaction (OER) with a low overpotential of 252 mV to achieve a current density of 10 mA cm⁻². The high oxygen evolution catalytic activity of O–CoSe₂-HNT can be attributed to the exposure of more active sites and optimization of the electronic structure via modifying oxygen on the catalyst surface. This work provides a new strategy to design efficient OER electrocatalysts with an oxygen-rich surface by a well-designed self-templating strategy.