Invited Paper GR+NS-MoA3
Opto-electronic Properties of Solution Processable Chemically Derived Graphene Oxide
Monday, October 18, 2010, 2:40 pm, Room Brazos
A solution based method that allows uniform and controllable deposition of reduced graphene oxide thin films with thicknesses ranging from a single monolayer up to several layers over large areas will be described. Transport of carriers in reduced GO is limited by the structural disorder. However, conductivity of 105 S/m and mobilities of ~ 10 cm2/V-s are sufficiently large for applications where inexpensive and moderate performance electronics are required. The oxidation treatment during synthesis of GO creates sp3 C-O sites where oxygen atoms are bonded in the form of various functional groups. GO is therefore a two dimensional network of sp2 and sp3 bonded atoms, in contrast to an ideal graphene sheet which consists of 100% sp2 carbon atoms. This unique atomic and electronic structure of GO, consisting of variable sp2/sp3 fraction, opens up possibilities for new functionalities. The most notable difference between GO and mechanically exfoliated graphene is the opto-electronic properties arising from the presence of finite band gap. In particular, the photoluminescence can be tuned from blue to green emission. The atomic and electronic structure along with tunable photoluminescence of graphene oxide at various degrees of reduction will be described.