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Hydrogen physisorption based on the dissociative hydrogen chemisorption at the sulphur vacancy of MoS₂ surface.

ABSTRACT: We provide a new insight that the sulphur-depleted MoS₂ surface can store hydrogen gas at room temperature. Our findings reveal that the sulphur-vacancy defects preferentially serve as active sites for both hydrogen chemisorption and physisorption. Unexpectedly the sulphur vacancy instantly dissociates the H₂ molecules and strongly binds the split hydrogen at the exposed Mo atoms. Thereon the additional H₂ molecule is adsorbed with enabling more hydrogen physisorption on the top sites around the sulphur vacancy. Furthermore, the increase of the sulphur vacancy on the MoS₂ surface further activates the dissociative hydrogen chemisorption than the H₂ physisorption.

SUBMITTER: Han SW

PROVIDER: S-EPMC5541097 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Hydrogen physisorption based on the dissociative hydrogen chemisorption at the sulphur vacancy of MoS2 surface.

Han Sang Wook SW Cha Gi-Beom GB Park Youngsin Y Hong S C SC

Scientific reports 20170802 1

We provide a new insight that the sulphur-depleted MoS2 surface can store hydrogen gas at room temperature. Our findings reveal that the sulphur-vacancy defects preferentially serve as active sites for both hydrogen chemisorption and physisorption. Unexpectedly the sulphur vacancy instantly dissociates the H2 molecules and strongly binds the split hydrogen at the exposed Mo atoms. Thereon the additional H2 molecule is adsorbed with enabling more hydrogen physisor ...[more]

PMID: 28769059

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