Plasma-induced large-area N,Pt-doping and phase engineering of MoS2 nanosheets for alkaline hydrogen evolution

Abstract

Phase engineering of transition metal dichalcogenides is of important significance for their electrocatalytic performance. Herein, we report a facile and scalable N₂-plasma strategy to promote the phase transformation of MoS₂ nanosheets from 2H to 1T with a remarkable conversion of ca. 62%. The plasma also favors the dissociation of the additional deposited Pt salts and the diffusion of Pt atoms into the MoS₂ nanosheets, which further improves the yield of the 1T phase to ca. 87%. The resulting N,Pt-MoS₂ nanosheet complexes immobilized on carbon cloth (CC) reveal excellent alkaline HER activity with a low overpotential of 38 mV at 10 mA cm⁻² and robust cycling stability. Refined structural characterization and theoretical calculations indicate that the deep doping of N and Pt elements regulates the electronic and coordination structures of MoS₂, and subsequently activate the sulfur sites to form emptier 2p_z orbitals that are favorable for water adsorption and dissociation. Notably, the plasma fabrication approach developed in this work can be readily applied to prepare large-area N,Pt-MoS₂ nanosheet-coated CC (32 cm × 16 cm) with a uniform 1T-phase and high hydrogen generation.