Preparation and characterization of fine indium tin oxide powders by a hydrothermal treatment and postannealing method

Indium tin oxide powder with an In to Sn mole ratio of 95:5 was successfully prepared from a coprecipitated In-Sn hydroxide gel by hydrothermal processing followed by calcination at relatively low temperatures (similar to 500 degrees C). Hydrothermal treatment of the In-Sn coprecipitated gel at 300 degrees C for 24 h led to the formation of a single phase of tin-doped indium oxyhydroxide (InOOH:Sn). Under hydrothermal conditions the oxyhydroxide phase appeared well crystallized with particles similar to 80 nm in size. Calcination of the oxyhydroxide phase above 450 degrees C in air yielded a substitutional-vacancy-type solid solution of In2Sn1-xO5-y.