Aggregation and resuspension of graphene oxide in simulated natural surface aquatic environments

作者：Hua Zulin; Tang Zhiqiang; Bai Xue^*; Zhang Jianan; Yu Lu; Cheng Haomiao

来源：Environmental Pollution, 2015, 205: 161-169.

DOI：10.1016/j.envpol.2015.05.039

• Graphene oxide
• Surface environment (cations, NOM, hydraulics)
• Aggregation
• Resuspension
• DLVO

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 Ca2+ (Mg2+) 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 Ca2+ (Mg2+), 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.

• 出版日期2015-10
• 单位河海大学