Modulating Trinary-Heterostructure of MoS2 via Controllably Carbon Doping for Enhanced Electrocatalytic Hydrogen Evolution Reaction

摘要

Understanding the phase transitions process of 2D transition metaldichalcogenides (2D-TMDs) from semiconducting (2H) to metallic (1T, 1T′)phase provides directionality for the iteration of hydrogen evolution catalysis.So far, the phase engineering methods are intensively explored, serving aspractical tools for discovering low-cost novel nanomaterials for electronic andelectrode devices in the realm of energy storage and catalysis. However, theheterostructures between 2H/1T, 2H/1T′, or 1T/1T′, functionalizing as criticalactive sites in the electrocatalytic process, are overlooked. Herein, a facilecarbon doping paradigms, enabling augmentation of MoS2 phase transition,together with density functional theory calculations and rationales to explainthe counterintuitive directionality of transitions is reported. The experimentand simulation results indicate that the existence of carbon as interstitialatoms is more favorable to the phase transition than the substitution atoms.The heterogeneous interfaces between 2H and 1T or 1T′ are more conduciveto charge transfer. As expected, the trinary-heterostructure nanofilmdisplays excellent electrocatalytic activities both in micro-electrochemicalmeasurements and conventional electrolytic cells. The results provide a freshinsight into the 2D-TMDs phase transition mechanism and guide for trinaryheterostructureelectrocatalysts for scalable production.