| The preparation technology and industrialization of research of flame synthesis nano-materials are maturing in The United States,Germany,Japan and other developed countries,the product monopolized most of the Chinese market.In China,research in this field is lagging behind,in order to solve the problems of parameters control,morphology and homogeneous of the product,and develope the flame synthesis technology and industrialization in China.This paper researched flame spray pyrolysis(FSP) synthesis and control of ZnO and conductive ZnO,at the same time studied about ZnO thin films.The main results obtained were summarized as followings:1.process-engineering of ZnO powders prepared by flame spray pyrolysis was detailed.Using the coflow diffusion flame burner with pressure atomization and gas atomization nozzle,through the FSP was prepared homogeneous nano-ZnO powders in 30 nm from zinc acetate ethanol solution.Analyzed the sample at different locations in flame,as well as precursor concentration and flame structure(CH4,O2,Ar) influenced on the particle size and homogeneous.With the Infrared high-speed thermographic system,we analyzed CH4,O2 and Ar impacted on the flame height and temperature field.2.Electrical conductivity and conductive mechanism of Al-doped ZnO were discussed.Considered the factors of cost and electrical conductivity,chose Al as a doping element. Using zinc-aluminum mixed as a precursor,prepared conductive Al-doped ZnO light-colored powders by FSP.Powders conductivity tests showed that when the Al doping ratio at 8.0 mol%(Zn0.92Al0.08O),the resistivity of conductive ZnO reached its lowest point,to 809Ω·cm,the particle size was about 30nm.3.Dense thin films constructed with uniform ZnO particles are prepared using quantitative filter paper as template and gas sensing properties were studied.ZnO thin film with dense surface morphology and uniform particle size of 30 nm can be prepared using the fast-speed quantitative filter paper template method,from zinc acetate dehydrate ethanol solution of 1.5 mol/L at the calcination temperature of 600℃.Synthesis of this method is faster and simpler.Through the gas-sensing properties tests,the ZnO thin films prepared from fast quantitative filter paper as a template has the best gas-sensing properties which is～120 to 205 ppm at 400℃.
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