CO2 bubble assisted layer-by-layer self-assembly of graphene oxide multilayer film

Graphene oxide (GO) multilayer films have been studied for various applications. The method of layer-by-layer (LbL) self-assembly is widely used for the preparation of multilayer films since it provides precise control of the nanoscopic features of the film. However, controlling nanoscopic features of GO film via conventional LbL self-assembly faces several challenges because of inherent aggregation behaviors of GO sheets in aqueous suspension. Herein, we report a novel method of CO2 bubble assisted LbL self-assembly of GO films. The adsorption kinetics of colloidal GO suspension was controlled via CO2 bubbles during LbL self-assembly. We characterized the effect of CO2 bubbles on the LbL assembly of GO sheets by analyzing the nanoscopic features of the multilayered GO films. The thickness, mass, surface morphology, and internal structure were analyzed by a profilometer, quartz crystal microbalance, scanning electron microscopy, atomic force microscopy, and photoluminescence spectroscopy.