R. Justin Joseyphus1, B. Jeyadevan ,
Received 1 March 2011; revised 11 May 2011; Accepted 8 July 2011. Available online 23 July 2011.
A low temperature synthesis technique to prepare indium tin oxide (ITO) nanoparticles by the polyol process is proposed. On examining the phase formation of ITO nanoparticles in polyols and alcohols such as ethylene glycol, trimethylene glycol, and 1-heptanol, it was found that ITO nanoparticles could be synthesized directly without any post--annealing treatments at 175 °C in 1-heptanol. The morphology of the particles is influenced by the type of polyol. The composition of Sn in the ITO system could be easily controlled by simply varying the In/Sn precursor ratio in 1-heptanol. The low temperature synthesis method has enabled the formation of highly crystalline ITO nanoparticles with diameters less than 25 nm even at annealing temperatures as high as 700 °C.
► Synthesis of ITO nanoparticles in various polyols attempted. ► Successful synthesis of composition controlled ITO nanoparticles in 1-heptanol at 175 °C. ► Morphology control of ITO nanoparticles via polyol type. ► Enhancement of crystallinity of less than 25 nm diameter ITO nanoparticles through high temperature annealing.