title: Graphene oxide papers modified by divalent ions-enhancing mechanical properties via chemical cross-linking.
abstract: Significant enhancement in mechanical stiffness (10-200%) and fracture strength (approximately 50%) of graphene oxide paper, a novel paperlike material made from individual graphene oxide sheets, can be achieved upon modification with a small amount (less than 1 wt %) of Mg(2+) and Ca(2+). These results can be readily rationalized in terms of the chemical interactions between the functional groups of the graphene oxide sheets and the divalent metals ions. While oxygen functional groups on the basal planes of the sheets and the carboxylate groups on the edges can both bond to Mg(2+) and Ca(2+), the main contribution to mechanical enhancement of the paper comes from the latter.
authors.affiliation: Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3111, USA.
authors.forename: Sungjin
authors.initials: S
authors.lastname: Park
authors.forename: Kyoung-Seok
authors.initials: KS
authors.lastname: Lee
authors.forename: Gulay
authors.initials: G
authors.lastname: Bozoklu
authors.forename: Weiwei
authors.initials: W
authors.lastname: Cai
authors.forename: Sonbinh T
authors.initials: ST
authors.lastname: Nguyen
authors.forename: Rodney S
authors.initials: RS
authors.lastname: Ruoff
mesh_terms: D003198:Computer Simulation; D003432:Cross-Linking Reagents / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D055119:Elastic Modulus; D006108:Graphite / Q000737:chemistry*; D006244:Hardness; D007477:Ions; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods; D010087:Oxides / Q000737:chemistry*; D010209:Paper; D010316:Particle Size; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D003432:Cross-Linking Reagents; D007477:Ions; D046911:Macromolecular Substances; D010087:Oxides; D006108:Graphite