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

Abstract

AbstractMolybdenum disulfide (MoS2) 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 MoS2 ultrathin nanosheets anchored on nitrogen‐doped multi‐walled carbon nanotubes (N−MoS2/N−CNTs) using urea as N‐doping reagent. It is demonstrated that the N species can expand the interlayer spacing of MoS2 and in‐situ substitute the S atoms in MoS2 lattices to create more structural defects, enabling highly exposed basal plane/edge sites. Simultaneously, N species in CNTs favor the interface coupling between N−MoS2 and N−CNTs, which can maintain structural stability and accelerate electron/proton reaction kinetics. Consequently, N−MoS2/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−MoS2/N−CNTs was demonstrated.