Synergistic effect between Er-doped MoS₂ nanosheets and interfacial Mo–N coupling phases for enhanced electrocatalytic hydrogen evolution

Hydrogen production via electrochemical water splitting is a promising and green technology. As one of the most representative transition metal sulfides layered materials, Molybdenum disulfide (MoS₂) has immense potential for the hydrogen evolution reaction (HER). We successfully prepared a nitrogen-doped carbon (NC) in situ-grown erbium-doped MoS₂ polyhedral structure (Er-MoS₂/NC) that incorporates an interfacial Mo–N coupling phase. The Er-MoS₂/NC catalyst possesses superior HER catalytic activity with a overpotential of 5 mV at the current density of 10 mA·cm^-2 and a small Tafel slope about 76 mV·dec-1 along with excellent stability. The synergistic effect of rare-earth doping and the interfacial Mo–N coupling phase effectively modifies the electronic structure of layered MoS₂ by increasing the exposed active sites and further lowering the hydrogen adsorption energy. The present work offers a new avenue for synthesizing multilayer nanostructured materials to improve the performance of sulfide-based materials for electrocatalytic HER. Graphical abstract: (Figure presented.).