(312a) Controlled Release of Molecular Intercalants in Graphene Oxide Films: Edge and Basal-Plane-Specific Kinetics of Planar, 1D Wrinkled, and 2D Crumpled Nanochannels

Substances encapsulation and release are important techniques in many applications, including flavor, fertilizer, pesticide, and drug deliveries. The matching of release and demand is critical, which requires the release to be slow or controlled. In a controlled release system, substances are sustained in the specific matrix and released into desired media under physical or chemical control. Several methods have been demonstrated to obtain controlled release vehicles using various 2D materials. This research shows the edge- and basal-plane-specific kinetics of planar, 1D wrinkled, and 2D crumpled nanochannels of graphene oxide films used to control the release rates of molecular intercalants pre-loaded into graphene oxide (GO) gallery spaces. We show the study on rhodamine B (RhB) dye, used as a model, show diffusive release rates in topography-related order. A pure RhB coated polymer substrate shows that approximately 80% of RhB was released in the first minute. RhB/GO intercalated. RhB within GO was slowly diffused; UV absorption shows a gradual increment of RhB in solution through 48 hrs, which reached equilibrium in 24 hrs. Here we will present the release rates and underlying pathways, including perpendicular and parallel to wrinkles. Moreover, we show the transport phenomena release profile of GO and citric acid intercalated experimental and modeling, which gives diffusivity coefficients of 9.92*10^-10 mm²/min for planar films, 1.07*10^-10 mm²/min for 1D wrinkles, and 2D 5.53*10^-10 mm²/min for 2D crumple. This type of fluidic-space manipulation should allow the intelligent design of 2D-material-based technologies such as time-release drug-eluting coatings.