Evidence for Electron Transfer between Graphene and Non-Covalently Bound pi-Systems
Journal article, 2020

Hybridizing graphene and molecules possess a high potential for developing materials for new applications. However, new methods to characterize such hybrids must be developed. Herein, the wet-chemical non-covalent functionalization of graphene with cationic pi-systems is presented and the interaction between graphene and the molecules is characterized in detail. A series of tricationic benzimidazolium salts with various steric demand and counterions was synthesized, characterized and used for the fabrication of graphene hybrids. Subsequently, the doping effects were studied. The molecules are adsorbed onto graphene and studied by Raman spectroscopy, XPS as well as ToF-SIMS. The charged pi-systems show a p-doping effect on the underlying graphene. Consequently, the tricationic molecules are reduced through a partial electron transfer process from graphene, a process which is accompanied by the loss of counterions. DFT calculations support this hypothesis and the strong p-doping could be confirmed in fabricated monolayer graphene/hybrid FET devices. The results are the basis to develop sensor applications, which are based on analyte/molecule interactions and effects on doping.

trication

doping

graphene

sensors

functionalization

Author

Steffen Brülls

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry, Physical Chemistry

Valentina Cantatore

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry 2

Zhenping Wang

Freie Universität Berlin

Eric Tam

Chalmers, Industrial and Materials Science, Materials and manufacture

Per Malmberg

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Jessica Stubbe

Freie Universität Berlin

Biprajit Sarkar

Freie Universität Berlin

University of Stuttgart

Itai Panas

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry 2

Jerker Mårtensson

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Siegfried Eigler

Freie Universität Berlin

Chemistry - A European Journal

0947-6539 (ISSN) 1521-3765 (eISSN)

Vol. 26 29 (Special Issue) 6694-6702

Subject Categories

Materials Chemistry

Theoretical Chemistry

Condensed Matter Physics

DOI

10.1002/chem.202000488

PubMed

32227533

More information

Latest update

7/3/2020 8