title: Rapid and direct conversion of graphite crystals into high-yielding, good-quality graphene by supercritical fluid exfoliation.
abstract: Graphene has attracted a great deal of attention in recent years due to its unusual electronic, mechanical, and thermal properties. Exploiting graphene properties in a variety of applications requires a chemical approach for the large-scale production of high-quality, processable graphene sheets (GS), which has remained an unanswered challenge. Herein, we report a rapid one-pot supercritical fluid (SCF) exfoliation process for the production of high-quality, large-scale, and processable graphene for technological applications. Direct high-yield conversion of graphite crystals to GS is possible under SCF conditions because of the high diffusivity and solvating power of SCFs, such as ethanol, N-methyl-pyrrolidone (NMP), and DMF. For the first time, we report a one-pot direct conversion of graphite crystals to a high yield of graphene sheets in which about 90-95% of the exfoliated sheets are < 8 layers with approximately 6-10% monolayers and the remaining 5-10% are > or = 10 layers.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Umezono 1-1-1, Tsukuba, Ibaraki 305-8568, Japan. dinesh.r@aist.go.jp
authors.forename: Dinesh
authors.initials: D
authors.lastname: Rangappa
authors.forename: Koji
authors.initials: K
authors.lastname: Sone
authors.forename: Mingsheng
authors.initials: M
authors.lastname: Wang
authors.forename: Ujjal K
authors.initials: UK
authors.lastname: Gautam
authors.forename: Dmitri
authors.initials: D
authors.lastname: Golberg
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
authors.forename: Masaki
authors.initials: M
authors.lastname: Ichihara
authors.forename: Itaru
authors.initials: I
authors.lastname: Honma