Novel synthesis of silica-graphene composites

Two of the most interesting materials in composite chemistry are silica and graphene. Both possess unique properties and features to make them suitable candidates as parent materials for a composite. The coupling of silica to graphene is demonstrated in this paper.This dissertation research presents three different methods to form silica-graphene composites. First method uses adsorption chemistry to bind graphene to diatom silica via physisorption interaction. The second employs deposition of graphene on diatom silica via metal-catalyzed chemical vapor deposition (CVD) technique. The last method which promotes covalent interaction between diatom silica, mineral silica and synthetic silica to graphene oxide (GO) is the hydrothermal process. This induces the simultaneous functionalization and partial reduction of GO in the presence of silica. The discovery of the hydrothermal technique is the highlight of the research. Results revealed that each composite presents different application possibilities. The GO-diatom silica can possibly be used as electrode for the detection of cationic biomolecules. The CVD graphene-diatom silica can be applied for biological templating to fabricate optoelectronics with 3D scaffolds while mesoporous silica-GO composite can possibly act as spacer to prevent restacking of graphene sheets