Preparation And Performance Of Graphene/Fiber Composite Materials By Capillary-Induced Self-Assembly Method

Due to the unique structure, excellent electrical, optical, mechanical, thermal performance and huge specific surface area, graphene has been widely applied to silicon-based electronics, catalyst carrier, biosensors, transparent conductive electrodes, battery materials, and so on in recent years, showing a promising application prospect. Based on the high electron mobility, good conductivity, good thermal stability, hydrophobicity and corrosion resistance of graphene, a majority of researches focus on the preparation of graphene coating materials and their applications so that a plenty of cut-edge works have been achieved. In this thesis, we overview the progress of gaphene coating in the field of electrical conduction, anti-static layer, microwave absorbing, sound absorption, heat conduction, anti-corrosion, wastewater treatment and so forth, then propose a novel grapheme coating approach according to the structural features of texitiles and fiber bundles. As a result, graphene/fiber composites are prepared and their wettability and conductivity are measured, then graphene-gauze for oil removal and graphene/glass fiber conductors are prepared. The details are as follows:1. Graphene oxide(GO) aqueous solution prepared by Hummes method with concentration of 1 mg/m L is uses as coating precursor. Driven by capillary force, GO solution is soaked by medical gauze and then assembled onto the cotton fibers of the guaze during the evaporation of the solvent. After 3 times deposition, GO-gauze composite is prepared and then reduced by hydrothermal treatment. The reduced GO(RGO)- guaze shows superhydrophobic and superoleophilic properties and can absorb soybean oil up to 11 times their own weight for the first time. About 50(±5) % adsorbed oil could be recycled by mechanical squeezing and a majority of them extracts from the reserve of large-diameter capillary action. The RGO-gauze maintained high structural stability and outstanding recyclability after eight cycles of oil removal. This RGO-gauze consumes a small quantity of graphene(0.6 g/m2) and can be produced in large scale, very suitable for application in the cleanup of oil spill and organic solvent effluent.2. Using nonconductive glass fiber as substate, GO nanosheets are assembled onto galss fiber through capillary self- assembly method. The thickness of GO layer is controlled by varing the assembly times, such as 1, 5, 10 and 20 times. After hydrothermal reduction, RGO-glass fibers are prepared. The electrical conductivity of RGO-glass fiber depends on the thickness of RGO coating layer, i.e., thicker RGO layer produces lower linear resistance. The electrical conductivity of RGO-GF20 is 22.87 S/cm, up to the value of a standard conductive fiber. The composilte fibers can keep the original electrical conductivity even bended to the angles of 60°, 120°, 180°, 360°, indicating their high flexibility. These conducitive RGO-glass fibers are in weave fabric for electrostatic shielding and anti-static application.