| Abstract
| - Cubic and spherical SrTiO3 particles with sizes of 80−1400 nm are obtained by precipitation from aqueous gel suspensions. The particles consist of ordered aggregates of building nanoblocks of 4−5 nm. The primary nanocrystals self-assemble in a highly oriented fashion, producing mesocrystals with single-crystal electron diffraction patterns.
- Cubic SrTiO3 particles are obtained by precipitation from an aqueous gel suspension. The gel suspensionis prepared by hydrolyzing a TiOCl2 solution with NaOH and adding SrCl2. The addition of citric acidleads to spherical particles. The particle size can be tailored in the range 80−1400 nm by varying thetemperature and the concentration. A careful control of the synthesis conditions is essential for producingparticles with a narrow size distribution. The results of HRTEM and ED investigations provide strongevidence that the oriented aggregation of small (4−5 nm) nanocrystals is the dominant growth mechanismfor the formation of the observed SrTiO3 particles. The primary nanocrystals self-assemble in a highlyoriented fashion, producing defective single-crystal particles. The above results show that the directionalaggregation process can be controlled by changing the temperature and concentration of the suspensionas well as by adding organic molecules, obtaining SrTiO3 particles with a controlled size and shape.
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