Solvothermal preparation and characteristics of Sn-doped In₂O₃

Abstract

Sn-doped In₂O₃ (ITO) nanopowders were prepared in ethanol solvent by solvothermal process. The effects of the solvothermal temperature, coprecipitation pH value and SnO₂ content on the products phase and microwave absorption were investigated by X-ray diffractometry and microwave reflectance. ITO nanopowders with cubic structure can be respectively prepared at 250 and 270°C for 6 h. The prepared product is InOOH or the mixture of InOOH and In₃Sn₄O₁₂ when the solvothermal temperature is below 250°C. With rising solvothermal temperature and prolonging time, the absorption of the ITO powders gradually decreases. The products are ITO nanopowders by coprecipitating at pH=9 or 11, but ITO powders with Sn₃O₄ at pH=6. The absorption of powders prepared at pH=6 is better than that at any other pH value. The products are all ITO nanopowders and crystal size reduces with increasing SnO₂ content. The microwave absorption of ITO nanopowders with SnO₂ content of 8% (mass fraction) is the best among samples with different SnO₂ contents.

Keywords

Sn-doped In₂O₃ (ITO) / solvothermal process / microwave absorption / preparation