Etching-assisted synthesis of Ni/Ni single atom anchored porous graphitic nanocarbon for improved hydrogen evolution reaction

Abstract

The development of single-atom catalysts (SACs) offers a novel strategy to minimize catalyst loadings while maintaining high electrocatalytic activity. Herein, a novel Ni/Ni single atom anchored porous graphitic nanocarbon (Ni/Ni_-SA–NC) is synthesized by an alkali-assisted etching approach combined with post-calcination protocol. It is manifested that the in situ formed AlN not only can function as a template for the generation of porous nanoarchitecture but can also serve as an anchoring agent for synthesized Ni–N_x species. Benefitting from the high specific surface area, abundant electroactive sites, and highly conductive graphitic carbon matrix, the fabricated Ni/Ni_-SA–NC displays superior HER performances with a quite low overpotential of 159 mV to achieve a current density of 10 mA cm⁻², far outperforming the Ni/C counterpart and long-term stability for over 50 h with unnoticeable current fluctuation in alkaline medium. Our work inspires the exploration of remarkable SACs electrocatalysts for cost-effective and large-scale hydrogen production in the energy conversion and storage field.