Research On Band Gap Regulation And Photoelectric Properties Of Doped Graphene Films

To promote graphene applications in the field of photoelectric detection,a simple method of bottom-up fabrication of graphene films was developed in this paper.It is a kind of technology of molecular self-assembly.Using heterogeneous element lattice doping control graphene band gap,hydrochloric acid was doped as Cl source and 2,4,6-triaminopyrimidine as N source preparation,we prepared Cl doped multilayer graphene films and N doped multilayer graphene films.Through physical property characterization,band gap change and the analysis of photoelectric response performance of two different doped graphene films photoelectric detector,the doped effect,band gap change and photoelectric response ability was analysed.Specific results are as follows:1.The Cl doped carbon source precursor was prepared by using hydrochloric acid as the chlorine source and glucose as the carbon source.The film was spun onto the quartz sheet as the substrate and then annealed in a vacuum furnace at a high temperature of 800?.Through characterization of Raman,TEM,XPS,FI-ATR and UV-Vis light absortion confirmed that the prepared graphene films is multilay graphene films with large numbers of flows.The band gap of Cl doped graphene films with three doping ratios were calculated,the values of band gap change with the doping ratio respectively.A simple Cl doped graphene thin film photodetector was prepared by covering a cross-finger electrode.The photoelectric properties of the film were studied which results showed that the photoelectric response of Cl doped graphene films is better with higher Cl doping ratio.A high response rate and detection rate to ultraviolet light is attained Cl doped graphene films photodetector of C/Cl=3/1 doping ratio.2.N doped multilayer graphene films were prepared with 2,4,6-triamine pyrimidine as the nitrogen source and glucose as the carbon source,and doped at different ratios by the same proces as the Cl doped graphene system.Through characterization of Raman,TEM,XPS,FI-ATR and UV-VIS light absortion confirmed that the prepared graphene films is multilayer graphene films with large numbers of flows.It also shows that nitrogen doping in graphene is effective,N atom enter the C lattice successfully.The N atom ratio in doped graphene film is closely related with the amount of doped 2,4,6-triaminepyrimidine which indicated the way regulating band gap by doping is feasible.The band gap of nitrogen-doped graphene films with three doping ratios changes in a narrow interval,so more accurate regulation could be attempted.A simple N doped graphene thin film photodetector was prepared by the same technology and its photoelectric response performance was tested.It was found that the photoelectric response performance of the photodetector prepared with low N doped graphene film was better.The photodetector test for the preparation of N doped graphene films with C/N=9/1 doping ratio showed that it has a higher response rate and detection rate to ultraviolet light...