Cecilia Mattevi1, Goki Eda1, Stefano Agnoli2, Stephen J. Miller1, K. Andre Mkhoyan3, Özgür Çelık4, Daniel Mastrogiovanni4, Gaetano Granozzi2, Eric Garfunkel4, Manish Chhowalla1
1Materials Science and Engineering Rutgers University, 607 Taylor Road Piscataway, New Jersey 08854 (USA).
2Department of Chemical Science, University of Padova, Via Marzolo 1, I-35131 Padova, Italy
3Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA
4Department of Chemistry and Chemical Biology Rutgers University, 607 Taylor Road Piscataway, New Jersey 08854 (USA)
Tóm tắt
AbstractA detailed description of the electronic properties, chemical state, and structure of uniform single and few‐layered graphene oxide (GO) thin films at different stages of reduction is reported. The residual oxygen content and structure of GO are monitored and these chemical and structural characteristics are correlated to electronic properties of the thin films at various stages of reduction. It is found that the electrical characteristics of reduced GO do not approach those of intrinsic graphene obtained by mechanical cleaving because the material remains significantly oxidized. The residual oxygen forms sp3 bonds with carbon atoms in the basal plane such that the carbon sp2 bonding fraction in fully reduced GO is ∼0.80. The minority sp3 bonds disrupt the transport of carriers delocalized in the sp2 network, limiting the mobility, and conductivity of reduced GO thin films. Extrapolation of electrical conductivity data as a function of oxygen content reveals that complete removal of oxygen should lead to properties that are comparable to graphene.
