Preparation And Properties Of ATO/Polymethylmethacrylate Composite Film

Nano antimony doped tin oxide （ATO） is an oxide semiconductor with excellentoptical and electrical properties, which is mainly used for flat-panel display, solar cell,touch screen, antistatic coating and so on. However, their application has been limitedfor the great brittleness, poor ductility and difficult mass production of tin dioxidetransparent conductive film.Inorganic-organic nanocomposite materials, combining theproperties of inorganic compounds, organic compounds and nano-materials, exhibitproperties superior to those of their separate components. In this paper, ATO-organicnanocomposite materials were prepared and their photoelectric properties wereinvestigated based on the preparation of ATO nano power and ATO nano film.ATO nano particles were synthesized by the sol-gel method, starting withSnC1₄·5H₂O and SnCl₃.The obtained nano particles were characterized by x-raydiffraction pattern （XRD）, fourier transform infrared （FTIR）, UV-visible transmissionspectrophotometer （UV-Vis） and four-probe resistivity tester. The results indicated thatthe average particles size of ATO was about10-20nm with excellent optical propertyand electrical conductivity. The preferable Sb/Sn atomic ratio was9%.Using sol-gel method with the starting reagents of SnCl₄and SnCl₃, antimony dopedtin oxide thin films with high transmittance and conductivity were synthesized. Themicrostructure, surface morphology, transmittance and conductivity properties werecharacterized by X-raydiffraction （XRD）, scanning electron microscope （SEM）,UV-visible spectrophotometer （UV-Vis） and four-probe resistivity tester. The effects ofcalcination temperature, calcination time, Sb doped content and thickness on themicrostructure, optical and conductivity properties of the ATO thin films wereinvestigated systematically.The optimum preparation condition of ATO films is that: Sbdoping content was8a.t%, adding2times the theoretical amount of ethanol as solvent,and spin coating for5layers and calcined at600℃. The obtained ATO film was lightblue with lowest resistivity （0.048·cm） and perfect transmittance （T>80%） in visiblelight range.A kind of PMMA （polymethylmethacrylate） based conductive composite filledwith nanoscaled ATO powder was prepared via in-situ polymerization. The effect ofATO powder pretreatment was observed from SEM photographs. The results show thatthe ATO powders were smaller and dispersed successfully by using silane coupling agent KH570（3%） and milling3hours. The influence of different ATO content addedPMMA/ATO composite were investigated, including conductive properties, thermalproperties and optical properties. The composite material volume resistivity reduced,PMMA thermal stability improved and red shift quantity also increased, but ultravioletvisible transmittance area reduced with the increase of the amount of ATO.