Nitrogen doped carbon layer-encapsulated Ni and NiMoN nanoparticles on carbon black substrate for efficient hydrogen evolution reaction

Highly efficient and low-cost catalysts for water electrolysis are crucial for the advancement of clean energy. In this study, an innovative hydrogen evolution reaction (HER) catalyst is synthesized, which consists of Ni and NiMoN nanoparticles coated by nitrogen-doped carbon layers and grown on a black pearl carbon substrate (denoted as NC@NiMoN NPs/BPC). The double carbon design-comprising a surface carbon coating layer and a bottom carbon substrate-modulates the electronic structure of NiMoN and facilitates the uniform dispersion of NiMoN NPs on BPC, endowing this hierarchical electrocatalyst with high activity and long durability. The electrochemical specific surface area of NC@NiMoN NPs/BPC is 42 times larger than that of NC@NiMoN without the BPC substrate. Moreover, this catalyst exhibits superior HER performance with low overpotentials of 11.3 and 74.6 mV at 10 and 100 mA cm −2 , respectively, outperforming the commercial Pt/C catalyst. Additionally, a typical alkaline water electrolyzer equipped with the NC@NiMoN NPs/BPC cathode shows negligible voltage decay after 250 h of continuous electrolysis, indicating excellent stability. This work provides not only an efficient hydrogen evolution electrocatalyst but also an innovative double-carbon strategy for the construction of efficient electrocatalysts for HER in water electrolysis.