Abstract:

Electrocatalytic hydrogen evolution reaction(HER) provides one of the most important pathways for the crisis of energy consumption. The research of both highly efficient as well as highly stable non-noble metal electrocatalysts is the key point of commercial application of HER. In this paper, through direct pyrolysis of bimetallic ZnCo zeolitic imidazolate frameworks(ZIFs), the electrocatalyst of evenly distributed Co nanoparticle coated by nitrogen-doped graphitic carbon(V-Co@NC, V, vacancy) could be easily prepared. The existence of Zn element in the precursor could prevent efficiently the aggregation of Co nanoparticles, and help for the formation of uniformly distributed Co nanoparticles. Such unique nanostructure prevents direct contact between cobalt and electrolyte, promots their durability. Meanwhile, the existence of nitrogen dopants enhances the conductivity of catalyst, and contributes to the HER activity greatly. As a result, as-prepared V-Co@NC catalyst exhibits high electrocatalytic activity towards HER in both acidic and alkaline electrolyte, meanwhile the activity remains stable even after 5000 cycles. These performances indicate promising commercial application of the V-Co@NC catalyst. This work opens a new way for the development of HER electrocatalysts with both high activity and stability.

Key words: hydrogen evolution reaction, electrocatalysis, non-noble metal electrocatlysts, high durability