title: Graphene phosphonic acid as an efficient flame retardant.
abstract: We report the preparation of graphene phosphonic acid (GPA) via a simple and versatile method and its use as an efficient flame retardant. In order to covalently attach phosphorus to the edges of graphene nanoplatelets, graphite was ball-milled with red phosphorus. The cleavage of graphitic C-C bonds during mechanochemical ball-milling generates reactive carbon species, which react with phosphorus in a sealed ball-mill crusher to form graphene phosphorus. Subsequent opening of the crusher in air moisture leads to violent oxidation of graphene phosphorus into GPA (highest oxidation state). The GPA is readily dispersible in many polar solvents, including neutral water, allowing for solution (spray) coating for high-performance, nontoxic flame-retardant applications.
authors.affiliation: School of Energy and Chemical Engineering/Low-Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), 100 Banyeon, Ulsan 689-897, South Korea.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Kim
authors.forename: In-Yup
authors.initials: IY
authors.lastname: Jeon
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Seo
authors.forename: Liming
authors.initials: L
authors.lastname: Dai
authors.forename: Jong-Beom
authors.initials: JB
authors.lastname: Baek