Park J.,Center for Superfunctional Materials |
Lee W.H.,Pohang University of Science and Technology |
Huh S.,Center for Superfunctional Materials |
Sim S.H.,SKKU Advanced Institute of Nanotechnology SAINT |
And 6 more authors.
Journal of Physical Chemistry Letters | Year: 2011
We have devised a method to optimize the performance of organic field-effect transistors (OFETs) by controlling the work functions of graphene electrodes by functionalizing the surface of SiO2 substrates with self-assembled monolayers (SAMs). The electron-donating NH2- terminated SAMs induce strong n-doping in graphene, whereas the CH 3-terminated SAMs neutralize the p-doping induced by SiO2 substrates, resulting in considerable changes in the work functions of graphene electrodes. This approach was successfully utilized to optimize electrical properties of graphene field-effect transistors and organic electronic devices using graphene electrodes. Considering the patternability and robustness of SAMs, this method would find numerous applications in graphene-based organic electronics and optoelectronic devices such as organic light-emitting diodes and organic photovoltaic devices. © 2011 American Chemical Society.