Toward boosted alkaline hydrogen evolution reaction: Covalent organic framework-derived N-doped carbon for highly dispersed cobalt nanoparticles

Abstract

The preparation of renewable hydrogen via electrocatalytic water splitting is a burgeoning strategy in developing sustainable energy. However, it is still a great challenge to prepare an efficient non-precious metal based electrocatalyst for hydrogen evolution in alkaline electrolysis. Herein, we describe a functional hydrogen evolution reaction (HER) electrocatalyst by the combination of soaking metal ions in covalent organic framework (COF) and high temperature calcination. Especially, the 2Co-NC-700 catalyst possesses large specific surface area, appropriate defective nature and structural distortion, thus it embodies outstanding HER catalytic activity with only an overpotential of 303 mV at the current density of 10 mA cm−2 in the solution of 1.0 M KOH. Moreover, the kinetics and durability are also confirmed. Theoretical calculations not only indicates that the stable configuration combined small-sized cobalt nanoparticles and nitrogen-doped carbon but also reveals the synergistic effect of multiple active sites, while the optimal active location that shows the lowest hydrogen adsorption free energy is a major contributor for excellent HER. This work not only offers a highly efficient HER catalyst in alkaline environment but also provides a novel approach to develop non-precious metal nitrogen-doped carbon materials derived from COF as HER electrocatalysts in alkaline media.