Graphene Thin Films With Controllable Fabrication And Their Performance, Application

Graphene, a novel sp2 carbon material with a two-dimensional(2D) nanostructure, which is first got from graphite by mechanical exfoliation method. Because its high light transmittance, excellent electron mobility as well as high filtration efficiency for macromolecules and small particulate, we design a new approach to fabricate controlled flexible conductive graphene thin films and develop a new kind of graphene / ceramic composite filter membrane material. In this paper, firstly, we have assembled graphene oxide film via the Langmuir-Blodgett method on a flexible polyester film substrate, then obtain flexible conductive graphene thin film by further reduction; in the process,we can also change its transmittance and conductivity by controlling the surface tension of the liquid level and the number of graphene film layers. Secondly, we propose an innovative liquid surface deposition method to prepare flexible graphene film,this way is to disperse evenly graphene oxide sheets which are prepared by chemical oxidation method on the surface,then the liquid surface gradually drop down to the substrate, thus it can make graphene oxide film lossless transfer to the substrate prepared in advance, subsequently, to achieve graphene film by mild reduction of hydroiodic. This method provides a good solution for the practical application,which is not only easy to operate, but also applicable to arbitrary substrates. Finally, we reported an oxidized graphene / ceramic composite filtration membrane,it uses the ceramic membrane as a substrate, coated with a layer of graphene oxide flakes on the inner and outer walls,this formed a dense graphene oxide "filtration system" on the surface of a ceramic film,so we can implement double filtering effect successfully while taking advantage of ceramic membranes and graphene oxide performance.