title: Doping graphene films via chemically mediated charge transfer.
abstract: Transparent conductive films (TCFs) are critical components of a myriad of technologies including flat panel displays, light-emitting diodes, and solar cells. Graphene-based TCFs have attracted a lot of attention because of their high electrical conductivity, transparency, and low cost. Carrier doping of graphene would potentially improve the properties of graphene-based TCFs for practical industrial applications. However, controlling the carrier type and concentration of dopants in graphene films is challenging, especially for the synthesis of p-type films. In this article, a new method for doping graphene using the conjugated organic molecule, tetracyanoquinodimethane (TCNQ), is described. Notably, TCNQ is well known as a powerful electron accepter and is expected to favor electron transfer from graphene into TCNQ molecules, thereby leading to p-type doping of graphene films. Small amounts of TCNQ drastically improved the resistivity without degradation of optical transparency. Our carrier doping method based on charge transfer has a huge potential for graphene-based TCFs.
authors.affiliation: Department of Electrical and Electronic Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro, Tokyo 152-8552, Japan. ishikawa.r.ab@m.titech.ac.jp.
authors.forename: Ryousuke
authors.initials: R
authors.lastname: Ishikawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Bando
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Adarsh
authors.initials: A
authors.lastname: Sandhu