Adsorption of P103 Nanoaggregates on Graphene Oxide Nanosheets: Role of Electrostatic Forces in Improving Nanosheet Dispersion

Graphene oxide (GO) nanosheet suspension is not stable in physiological ionic fluids. To improve stability, surfactants such as Pluronic 103 (P103) have been tested. Going further, this work investigated whether conferring positive surface charge to the surfactant may adsorption ability of P103 micelles on GO sheets. Positive was induced by adding dodecyltrimethylammonium bromide (DTAB, a cationic surfactant) micelles. Subsequent changes aggregation parameters were through dynamic light scattering and small-angle neutron studies. DTAB incorporation accompanied steady increase ζ potential mixed micelle formation. At high density, interaction between adjacent head groups distorted, which led dissociation Structural developments during sheet (mass fractal formation) monitored terms features aggregates. These fractals emerged result electrostatic interactions. Our observations point toward existence small-sized building blocks at low concentration (≤4 mM). With superior adsorption, are expected occupy intersheet space maintain hydration layer. However, higher (≥10 mM), dissociate produce DTAB-rich unimers P103-rich loose point, sheets tend aggregate solvent, regardless