Structural Engineering of Nitrogen‐Doped MoS2 Anchored on Nitrogen‐Doped Carbon Nanotubes towards Enhanced Hydrogen Evolution Reaction

Abstract Molybdenum disulfide (MoS 2 ) has emerged as an attractive non‐noble‐metal electrocatalyst for hydrogen evolution reaction (HER), but its performance is limited by scarce active sites and poor conductivity. Herein, we construct a hetero‐structure of nitrogen‐doped MoS 2 ultrathin nanosheets anchored on nitrogen‐doped multi‐walled carbon nanotubes (N−MoS 2 /N−CNTs) using urea as N‐doping reagent. It is demonstrated that the N species can expand the interlayer spacing of MoS 2 and in‐situ substitute the S atoms in MoS 2 lattices to create more structural defects, enabling highly exposed basal plane/edge sites. Simultaneously, N species in CNTs favor the interface coupling between N−MoS 2 and N−CNTs, which can maintain structural stability and accelerate electron/proton reaction kinetics. Consequently, N−MoS 2 /N−CNTs exhibits the in‐depth enhancement of HER activity with a low onset potential (77 mV), small Tafel slope (40.5 mV dec −1 ) and excellent cycling stability. Furthermore, the essential relationship between the N‐doping concentration and HER activity of N−MoS 2 /N−CNTs was demonstrated.