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Impact of Graphene Work Function on the Electronic Structures at the Interface between Graphene and Organic Molecules.

ABSTRACT: The impact of graphene work function (WF) on the electronic structure at the graphene/organic interface has been investigated. WF manipulation of graphene is realized using self-assembled monolayers (SAMs) with different end groups. With this method, the upper surface of the functionalized graphene remains intact, and thus precludes changes of molecular orientation and packing structures of subsequently deposited active materials. The WF of NH₂-SAM functionalized graphene is ~3.90 eV. On the other hand, the WF of graphene increases to ~5.38 eV on F-SAM. By tuning the WF of graphene, an upward band bending is found at the ZnPc/graphene interface on F-SAM. At the interface between C₆₀ and NH₂-SAM modified graphene, a downward band bending is observed.

SUBMITTER: Wang H

PROVIDER: S-EPMC6723703 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Impact of Graphene Work Function on the Electronic Structures at the Interface between Graphene and Organic Molecules.

Wang Haitao H Yang Xiangdong X Dou Weidong W Wang Peng P Ye Quanlin Q Yang Xuxin X Li Baoxing B Mao Hongying H

Nanomaterials (Basel, Switzerland) 20190807 8

The impact of graphene work function (WF) on the electronic structure at the graphene/organic interface has been investigated. WF manipulation of graphene is realized using self-assembled monolayers (SAMs) with different end groups. With this method, the upper surface of the functionalized graphene remains intact, and thus precludes changes of molecular orientation and packing structures of subsequently deposited active materials. The WF of NH<sub>2</sub>-SAM functionalized graphene is ~3.90 eV. ...[more]

PMID: 31394772

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