title: The realistic domain structure of as-synthesized graphene oxide from ultrafast spectroscopy.
abstract: Graphene oxide (GO) is an attractive alternative for large-scale production of graphene, but its general structure is still under debate due to its complicated nonstoichiometric nature. Here we perform a set of femtosecond pump-probe experiments on as-synthesized GO to extrapolate structural information in situ. Remarkably, it is observed that, in these highly oxidized GO samples, the ultrafast graphene-like dynamics intrinsic to pristine graphene is completely dominant over a wide energy region and can be modified by the localized impurity states and the electron-phonon coupling under certain conditions. These observations, combined with the X-ray photoelectron spectroscopy analysis and control experiments, lead to an important conclusion that GO consists of two types of domain, namely the carbon-rich graphene-like domain and the oxygen-rich domain. This study creates a new understanding of the realistic domain structure and properties of as-synthesized GO, offering useful guidance for future applications based on chemically modified/functionalized graphenes.
authors.affiliation: Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China. qunzh@ustc.edu.cn
authors.forename: Qun
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hongjun
authors.initials: H
authors.lastname: Zheng
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Geng
authors.forename: Shenlong
authors.initials: S
authors.lastname: Jiang
authors.forename: Jing
authors.initials: J
authors.lastname: Ge
authors.forename: Kaili
authors.initials: K
authors.lastname: Fan
authors.forename: Sai
authors.initials: S
authors.lastname: Duan
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Luo
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic; D006108:Graphite / Q000138:chemical synthesis* / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D013057:Spectrum Analysis; D013997:Time Factors
chemical_list: D010087:Oxides; D006108:Graphite; D001151:Arsenic; D010100:Oxygen