The Preparation And Photoelectric Properties Of Functional Graphene Oxide Quantum Dots

As one of the most important information carriers,photodetectors are the most widely used electronic devices in optical information feedback applications.The rapid development of nanotechnology has provided new technology and means to break through the bottleneck of traditional photodetector materials.In recent years,unprecedented hot research on carbon materials has also made great breakthroughs and progress.However,the existing optoelectronic detection materials still face many problems,such as limited performance control methods,scarce resources and so on.Graphene oxide was prepared by Hummers method.Hydrobromic acid,hydrochloric acid and hydrofluoric acid functionalized graphene oxide were prepared by hydrothermal reaction.Atomic force microscopy(AFM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),scanning electron microscopy(EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible-infrared(UV-Vis-NIR)absorption spectroscopy,fluorescence spectroscopy(PL?PLE),Raman spectroscopy and Keithley 2400 test system were used.The prepared graphene oxide and bromine doped graphene oxide materials and devices were characterized,tested and analyzed.The research contents and main results are as follows:1.Using flake graphite as carbon source,sulfuric acid as solvent medium,potassium permanganate and sodium nitrate as oxidant,the oxidant can be oxidized step by step in three stages:ice bath stage,35 middle temperature stage and 60 high temperature stage.The oxidant can be inserted into graphite sheets to increase the spacing of graphite sheets,and at the same time hydroxyl,carboxyl,ketone and other oxygen-containing functional groups can be formed on graphite oxide.Graphene oxide with large transverse size,controllable layer number and oxidation degree was prepared.2.Functionalized graphene oxide quantum dots were prepared by hydrothermal reaction with hydrobromic acid,hydrochloric acid,hydrofluoric acid and GO as raw materials,and their structures and photoelectric properties were studied.3.The dispersion and adhesion of GO were studied by inkjet printing,and the GO film formation was further studied by spin coating.GO printing ink prepared by increasing power and prolonging ultrasonic time shows better dispersion and adhesion,more complete printed graphics and more uniform ink production.In addition,a more intuitive and convenient spin coating method was used to study GO film formation.It was found that the GO aqueous solution could form a dense and continuous film on both the silicon wafer and the quartz substrate after one spin coating.4.A simple interdigital electrode device was fabricated to study the photoelectric conversion performance of GO.The results show that the response rate of GO is the highest when the power density of GO is 0.672 mW/cm2 and the power density of GO is 0.109 mW/cm2.When the power density of GO is 0.109 mW/cm2,the maximum D*is 5.7*1014 Jones.5.A simple interdigital electrode device was fabricated to study the photoelectric conversion performance of Br-GO quantum dots.Compared with 850 nm near infrared light,the calculated response R and D*of 365 nm near ultraviolet light source are improved,the response rate is increased by nearly six times,and the detection rate is increased by nearly one order of magnitude.