• 文献标题:   Evidence for Electron Transfer between Graphene and Non-Covalently Bound pi-Systems
  • 文献类型:   Article
  • 作  者:   BRULLS SM, CANTATORE V, WANG ZP, TAM PL, MALMBERG P, STUBBE J, SARKAR B, PANAS I, MARTENSSON J, EIGLER S
  • 作者关键词:   doping, functionalization, graphene, sensor, trication
  • 出版物名称:   CHEMISTRYA EUROPEAN JOURNAL
  • ISSN:   0947-6539 EI 1521-3765
  • 通讯作者地址:   Free Univ Berlin
  • 被引频次:   0
  • DOI:   10.1002/chem.202000488 EA APR 2020
  • 出版年:   2020

▎ 摘  要

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.