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Cross-plane transport in a single-molecule two-dimensional van der Waals heterojunction.

ABSTRACT: Two-dimensional van der Waals heterojunctions (2D-vdWHs) stacked from atomically thick 2D materials are predicted to be a diverse class of electronic materials with unique electronic properties. These properties can be further tuned by sandwiching monolayers of planar organic molecules between 2D materials to form molecular 2D-vdWHs (M-2D-vdWHs), in which electricity flows in a cross-plane way from one 2D layer to the other via a single molecular layer. Using a newly developed cross-plane break junction technique, combined with density functional theory calculations, we show that M-2D-vdWHs can be created and that cross-plane charge transport can be tuned by incorporating guest molecules. The M-2D-vdWHs exhibit distinct cross-plane charge transport signatures, which differ from those of molecules undergoing in-plane charge transport.

SUBMITTER: Zhao S

PROVIDER: S-EPMC7259930 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Cross-plane transport in a single-molecule two-dimensional van der Waals heterojunction.

Zhao Shiqiang S Wu Qingqing Q Pi Jiuchan J Liu Junyang J Zheng Jueting J Hou Songjun S Wei Junying J Li Ruihao R Sadeghi Hatef H Yang Yang Y Shi Jia J Chen Zhaobin Z Xiao Zongyuan Z Lambert Colin C Hong Wenjing W

Science advances 20200529 22

Two-dimensional van der Waals heterojunctions (2D-vdWHs) stacked from atomically thick 2D materials are predicted to be a diverse class of electronic materials with unique electronic properties. These properties can be further tuned by sandwiching monolayers of planar organic molecules between 2D materials to form molecular 2D-vdWHs (M-2D-vdWHs), in which electricity flows in a cross-plane way from one 2D layer to the other via a single molecular layer. Using a newly developed cross-plane break ...[more]

PMID: 32524003

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