title: Improving the electrical properties of graphene layers by chemical doping.
abstract: Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO3) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO3. The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO3provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Muhammad Farooq
authors.initials: MF
authors.lastname: Khan
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Muhammad Zahir
authors.initials: MZ
authors.lastname: Iqbal
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Muhammad Waqas
authors.initials: MW
authors.lastname: Iqbal
authors.affiliation: Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, Korea.
authors.forename: Jonghwa
authors.initials: J
authors.lastname: Eom
keywords: Raman spectroscopy; chemical doping; electrical properties; graphene; potassium nitrate