Study On Synthesis And Properties Of Cubic Indium Tin Oxide Nanoparticles

Excellent photoelectric properties make indium tin oxide（ITO） widely used in electronic components,gaseous substances and pressure monitoring,functional glass and many other materials and products.ITO is obtained by doping indium oxide and has the same crystal type with indium oxide,including cube-phase crystal ITO（c-ITO）as raw material of high-performance ITO target.In this paper,the experimental process of preparing ITO powder by microemulsion method was optimized by orthogonal experiment.The ellipsoid c-ITO powder was prepared by compound surfactant system,and the microscopic mechanism of the experiment was analyzed.c-ITO nanoparticles were synthesized by solvothermal method and reaction conditions were changed.In this experiment,the performance of c-ITO changed with the change of experimental conditions,and finally the cubic ITO nanoparticles were successfully synthesized.After this,the microscopic formation process of c-ITO was studied.ITO powder was prepared by microemulsion method,in which two different fatty alcohol polyoxyethylene ether（AEO-3 and MOA-5）were used as surfactants,short chain alcohol n-propanol as cosurfactants,and ammonia water as precipitant.Using the scientific calculation method of range and variance to deal with experimental data,it is concluded that when the mass ratio of AEO-3 and MOA-5 is 1:1,the best experimental process is as follows:m（AEO-3&MOA-5）/m（co-sur）=5:3,n(In³⁺)/n（ammonia）=1:20,calcination temperature and time are 700℃,4 h,respectively.The effect of single variable on the properties of ITO powder was studied.The results showed that the surface calcination temperature had the most significant effect on the properties of ITO powder.Under the best experimental techniques,the c-ITO powder is ellipsoidal with 100 nm long diameter and 60 nm short diameter.The resistivity is 0.3675Ω·cm,and the oxygen vacancy content is 27.39%.The band gap is3.8 e V.ITO powder was prepared by one-step solvothermal method.Three organic solvents,ethylene glycol,diethylene glycol and glycerol,were chosen as the solvent system by solvothermal method,and the relationship between the composition of solvent and reaction conditions and the properties of ITO powder was explored.The final conclusion:the selected solvent system is ethylene glycol-diethylene glycol system and V_{（ethylene glycol:diethylene glycol）}is 3:1,The holding time and temperature are 24 h and 250℃respectively.The influence of different experimental parameters on experimental results was systematically studied.The results showed that the reaction temperature was the key to determine the complete reaction of raw materials,and the holding time had significant relationship with the morphology of ITO powder.Under the optimum conditions,the cubic c-ITO powder with particle size of 50 nm was prepared,and its resistivity was 1.05Ω·cm,oxygen vacancy content was26.54%,and energy band gap was 3.65 eV.