posted on 2020-07-31, 18:34authored byChan Ho Park, Won-Tae Koo, Young Jun Lee, Yoon Hwa Kim, Jiyoung Lee, Ji-Soo Jang, Hongseok Yun, Il-Doo Kim, Bumjoon J. Kim
For
rapid hydrogen gas (H2) sensing, we propose the
facile synthesis of the hollow structure of Pt-decorated molybdenum
disulfide (h-MoS2/Pt) using ultrathin (mono- or few-layer)
two-dimensional nanosheets. The controlled amphiphilic nature of MoS2 surface produces ultrathin MoS2 NS-covered polystyrene
particles via one-step Pickering emulsification.
The incorporation of Pt nanoparticles (NPs) on the MoS2, followed by pyrolysis, generates the highly porous h-MoS2/Pt. This hollow hybrid structure produces sufficiently permeable
pathways for H2 and maximizes the active sites of MoS2, while the Pt NPs on the hollow MoS2 induce catalytic
H2 spillover during H2 sensing. The h-MoS2/Pt-based chemiresistors show sensitive H2 sensing
performances with fast sensing speed (response, 8.1 s for 1% of H2 and 2.7 s for 4%; and recovery, 16.0 s for both 1% and 4%
H2 at room temperature in the air). These results mark
the highest H2 sensing speed among 2D material-based H2 sensors operated at room temperature in air. Our fabrication
method of h-MoS2/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.