Study Of The Preparation Of Doped Antimony Tin Oxide (ATO) And Their Properties

Antimony doped tin oxide referred to as ATO is transparent conductive oxide material. In recent years, ATO materials have a wide application in many fields and become a new type of functional material because of its excellent properties such as good chemical stability, high electrical conductivity and high transparency.At present, the most common way to produce ATO is a liquid phase method. This method has many advantages such as simple process and low manufacture cost. However, during the solution synthesis of ATO particles, the present of water can result in the hydrolysis of metal ions, the serious agglomeration of particles and even the faster crystal growth, thus leading to the lower purity and a larger average particle size of the obtained ATO powders. Moreover, the commonly used precipitant is ammonia which is volatile and hard to storage and transport, therefore, this will limit its application. Considering these these disadvantages of liquid phase method, our study would be to explore a novel approach to overcome the above-mentioned disadvantages so as to prepare ATO materials with a higher performance.In this study, we would produce ATO particles by using diffusion co-precipitation method, solvothermal method, direct co-precipitation method. SnCl4·5H2O and SbCl3 would be used as raw materials while alcohol would be used as the solvent in these three methods. The final products were characterized by using Fourier-transform infrared spectrometer, X-ray diffraction, scanning electron microscopy, four point probe method and so on. Based on the above characterization, we have carried out a comparative study for them so as to find a best preparation method to synthesize ATO powder. And meanwhile through further characterization of DSC-TGA and IR we have deeply studied the formation mechanism of ATO associated with the above-mentioned three methods.Because the water in the solvent will seriously affect the performance of ATO nanoparticles, the influence of water content on the ATO materials would also be discussed in this study. The effect of different doping amount on the ATO powder particle size, resistivity and microstructure would be investigated so as to determine the optimal doping amount to obtain small particle size, low resistance of ATO materials.The results showed that the conductivity and dispersivity of the obtained ATO nanoparticles by using the diffusion co-precipitation method were the best among these three methods. When alcohol was used as the solvent, the obtained ATO precursor was in a form of coordination compounds, whose crystal water and organics would decompose and evaporate with increasing temperature during calcination and then the final ATO product would be obtained after calnication. The results showed that, the average grain size and electrical resistivity decreased with the increased amount of antimony doped first then increased. The presence of water in the solvent would lead to the agglomeration of ATO particles and hydrolysis of metal ions, which is not conducive to the preparation of ATO powder with small particle size and low resistance.Our study indicated that the doped antimony could successfully fuse into the tin oxide lattice using all the three methods, and that the calcined ATO could form a single solid solution.The finally obtained ATO nano powder with high quality presented a conduvtivity of 26.67 s.cm-1, a particle size of 5-10 nm and a productivity of 88%, respectively. This research would provide a simple, economical approach to prepare ATO powder with a small average particle size, a low resistance and good dispersity.