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

Abstract

Molybdenum 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.

Flexible Humidity Sensor Based on a Graphene Oxide–Carbon Nanotube-Modified Co3O4 Nanoparticle-Embedded Laser-Induced Graphene Electrode

“…Despite undergoing treatments such as carboxylation and ultrasonic oscillation dispersion, certain MWCNTs persist in localized clusters within the stratified matrix of GO. Detailed examination through HRTEM imaging, as illustrated in Figure i, enables the clear visualization of lattice fringes on the MWCNTs, revealing an interplanar spacing of around 0.34 nm consistent with established literature findings. , …”

“…Detailed examination through HRTEM imaging, as illustrated in Figure 2i, enables the clear visualization of lattice fringes on the MWCNTs, revealing an interplanar spacing of around 0.34 nm consistent with established literature findings. 52,53 The elemental compositions and chemical states of the humidity-sensitive material and the composite electrode are scrutinized through X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The full-range XPS spectrum of the GO−MWCNT material (Figure S2) reveals the presence of C and O elements within the humidity-sensitive material.…”