Fuchuan Huang

Graphene/Ionic Liquid Composite Films and Ion Exchange

Wettability of graphene is adjusted by the formation of various ionic surfaces combining ionic liquid (IL) self-assembly with ion exchange. The functionalized ILs were designed and synthesized with the goal of obtaining adjustable wettability. The wettability of the graphene surface bearing various anions was measured systematically. The effect of solvent systems on ion exchange ratios on the graphene surface has also been investigated. Meanwhile, the mechanical properties of the graphene/IL composite films were investigated on a nanometer scale. The elasticity and adhesion behavior of the thin film was determined with respected to the indentation deformation by colloid probe nanoindentation method. The results indicate that anions played an important role in determining graphene/IL composite film properties. In addition, surface wetting and mechanics can be quantitatively determined according to the counter-anions on the surface. This study might suggest an alternate way for quantity detection of surface ions by surface force.

Preparation and Mechanics of Nanotextures on Adapting a Low Adhesive Surface Using Local Oxidation Nanolithography

This paper describes an application for atomic force microscopy to the fabrication of nanotextures with various features on a GaAs surface by local oxidation nanolithography (LON). By controlling the geometrical shapes and surface coverage of the nanotexture, the surface adhesion can be adjusted to a low adhesive surface. The influence of environmental conditions, such as relative humidity and temperature on adhesion behavior, was studied. An optic heater was employed to minimize thermal effect on an atomic force microscope (AFM) cantilever and PbZrTiO3 scanner. In our study, AFM is used for both fabrication and characterization. LON allows the fabricated nanotextures to be altered in situ without the need to change masks or repeat the entire fabrication process. Furthermore, the nanoadhesion characterization of nanotextures on a GaAs surface was investigated with a colloidal probe method.