Hydrogen Sensors Based on MoS2 Hollow Architectures Assembled by Pickering Emulsion

摘要

For rapid hydrogen gas (H_(2)) sensing, we propose the facile synthesis of the hollow structure of Pt-decorated molybdenum disulfide (h-MoS_(2)/Pt) using ultrathin (mono- or few-layer) two-dimensional nanosheets. The controlled amphiphilic nature of MoS_(2) surface produces ultrathin MoS_(2) NS-covered polystyrene particles via one-step Pickering emulsification. The incorporation of Pt nanoparticles (NPs) on the MoS_(2), followed by pyrolysis, generates the highly porous h-MoS_(2)/Pt. This hollow hybrid structure produces sufficiently permeable pathways for H_(2) and maximizes the active sites of MoS_(2), while the Pt NPs on the hollow MoS_(2) induce catalytic H_(2) spillover during H_(2) sensing. The h-MoS_(2)/Pt-based chemiresistors show sensitive H_(2) sensing performances with fast sensing speed (response, 8.1 s for 1% of H_(2) and 2.7 s for 4%; and recovery, 16.0 s for both 1% and 4% H_(2) at room temperature in the air). These results mark the highest H_(2) sensing speed among 2D material-based H_(2) sensors operated at room temperature in air. Our fabrication method of h-MoS_(2)/Pt structure through Pickering emulsion provides a versatile platform applicable to various 2D material-based hollow structures and facilitates their use in other applications involving surface reactions.