Surface Modification of Graphene Oxide with Pyrene Derivatives and their Photo-Switching Behaviors

Abstract

The characteristics of surface and interface of nanocomposites are favor for exerting some functional properties and widening new applications. Some low-dimensional materials generally have abundant chemical groups and reaction activities. These surface chemical groups of nanomaterials provide a large platform to develop new nanocomposites and applications by surface chemical reaction and surface reconstruction of another kind of materials. Among so many hot-fields materials, graphene and its nanocomposite are developed rapidly. The graphene oxide not only has good charge transferring property, but also has abundant chemical groups on its surface, such as, -COOH, -OH and epoxide group. Therefore, graphene oxide is a good candidate substrate for further constructing other functional materials in nanoscale. The graphene oxide and pyrene derivatives were selected as representative materials for studies. Assembly of pyrene containing –NH2 groups on the surface of graphene oxide was carried out. A series of characterizations were performed by SEM (scanning electron microscopy), TEM (transmission electron microscopy), the FTIR (Fourier-Transform Infrared ) spectra, The UV-Vis (Ultra-violet visible spectroscopy), photoluminescence spectra, et al. The results indicated that the UV-Vis of nanocomposite was almost covered the whole region of visible light, and the results of PL showed strong fluorescence quenching. There was strong interaction between the graphene oxide and pyrene. The photoconductivity response to weak visible light and 808 nm laser were studied based on interdigital electrodes of Au on flexible PET(polyethylene terephthalate) film substrate with casting method. The results showed that graphene oxide modified with pyrene derivatives exhibited that the photocurrent increased obviously to visible light, and photoresponse to weak 808 nm laser emerged photo-switching behavior. It would be developed the light detector to NIR, biomimetic fields or external stimuli driven nanocarriers for biomedical fields, et al.