Novel Seed-Assisted Synthesis of Ito Submicro-Cubes and Their Resistivity

Indium tin oxide (ITO), which is a promising n-type conducting oxide material, shows great prospects in photoelectric device applications. In this work, the ITO submicro-cubes have been synthesized by seed-assisted coprecipitation method. The effects of seed addition, In3+ concentration, aging time, reaction temperature and calcination temperature on the resistivity and microstructure of ITO powders were investigated by single factor experiment. It is interesting to note that the resistivity of ITO submicro-cubes is lower due to face-to-face contact among cubic particles and well dispersion. Then the orthogonal experiment design was applied to obtain the optimal preparation process combination that was as follows: seed addition was 6 wt%, In3+ concentration was 0.06 mol/L, reaction temperature was 80 ℃, and calcination temperature was 750 ℃. Afterwards, thermal decomposition of ITO precursor, phase composition, morphology and resistivity of the optimal sample were characterized systematically. The results illustrated that the precursor and sample were well matched with cubic In(OH)3 and In2O3 standard phase. The single-crystal particles exhibited regular cubic shape with nearly size of 500 nm and low resistivity of 0.81 Ω·cm under the optimal preparation process combination. In addition, the synthesis mechanism of ITO submicro-cubes by seed-assisted coprecipitation method was analyzed and discussed. The addition of seed particles provides more effective nucleation sites and promotes the formation of submicron ITO particles. The resultant ITO submicro-cubes showing low resistivity present potential application in photoelectric devices