Probing charge transfer between molecular semiconductors and graphene

Aleksandar Matkovic, Markus Kratzer, Benjamin Kaufmann, Jasna Vujin, Rados Gajić, Christian Teichert

Research output: Contribution to journalArticleResearchpeer-review

15 Citations (Scopus)

Abstract

The unique density of states and exceptionally low electrical noise allow graphene-based field effect devices to be utilized as extremely sensitive potentiometers for probing charge transfer with adsorbed species. On the other hand, molecular level alignment at the interface with electrodes can strongly influence the performance of organic-based devices. For this reason, interfacial band engineering is crucial for potential applications of graphene/organic semiconductor heterostructures. Here, we demonstrate charge transfer between graphene and two molecular semiconductors, parahexaphenyl and buckminsterfullerene C60. Through in-situ measurements, we directly probe the charge transfer as the interfacial dipoles are formed. It is found that the adsorbed molecules do not affect electron scattering rates in graphene, indicating that charge transfer is the main mechanism governing the level alignment. From the amount of transferred charge and the molecular coverage of the grown films, the amount of charge transferred per adsorbed molecule is estimated, indicating very weak interaction.
Original languageEnglish
Article number7: 9544
Pages (from-to)1-9
Number of pages9
JournalScientific reports (London : Nature Publishing Group)
Volume7
DOIs
Publication statusPublished - 25 Aug 2017

Keywords

  • graphene
  • organic semiconductors
  • charge transfer

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