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

摘要

Phase engineering of transition metal dichalcogenides is of important significance for their electrocatalytic performance. Herein, we report a facile and scalable N-2-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 x 16 cm) with a uniform 1T-phase and high hydrogen generation.