title: Aggregation and resuspension of graphene oxide in simulated natural surface aquatic environments.
abstract: A series of experiments were performed to simulate the environmental behavior and fate of graphene oxide nanoparticles (GONPs) involved in the surface environment relating to divalent cations, natural organic matter (NOM), and hydraulics. The electrokinetic properties and hydrodynamic diameters of GONPs was systematically determined to characterize GONPs stability and the results indicated Ca(2+) (Mg(2+)) significantly destabilized GONPs with high aggregate strength factors (SF) and fractal dimension (FD), whereas NOM decreased aggregate SF with lower FD and improved GONPs stability primarily because of increasing steric repulsion and electrostatic repulsion. Furthermore, the GONPs resuspension from the sand bed into overlying water with shear flow confirmed that the release would be restricted by Ca(2+) (Mg(2+)), however, enhanced by NOM. The interaction energy based on Derjaguin-Landau-Verwey-Overbeek theory verifies the aggregation and resuspension well. Overall, these experiments provide an innovative look and more details to study the behavior and fate of GONPs.
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Zulin
authors.initials: Z
authors.lastname: Hua
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Tang
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China. Electronic address: baixue@hhu.edu.cn.
authors.forename: Xue
authors.initials: X
authors.lastname: Bai
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Jianan
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Lu
authors.initials: L
authors.lastname: Yu
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Haomiao
authors.initials: H
authors.lastname: Cheng
mesh_terms: D002413:Cations, Divalent / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D057446:Hydrodynamics; D053758:Nanoparticles / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D055672:Static Electricity; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D010087:Oxides; D014874:Water Pollutants, Chemical; D006108:Graphite
keywords: Aggregation; DLVO; Graphene oxide; Resuspension; Surface environment (cations, NOM, hydraulics)