Synthesis of yttrium aluminum garnet nanoparticles in confined environment II: Role of the thermal treatment on the composition and microstructural evolution

A possible growth mechanism of YAG nanoparticles is discussed on the basis of observed particle microstructure and morphology. The results indicate that, applying this sequence of thermal treatments, the formation of the garnet phase takes place with the formation of yttria nuclei that grow preferentially in one direction. The growth takes place via two processes: at low temperature the nuclei evolve to the garnet phase by following the oriented attachment mechanism, at higher temperatures by the Kirkendall effect accounting for the morphological modification. The proposed synthesis and thermal treatments, by favoring one or the other growth mechanisms, allowed attaining a fine control on nanoparticles features thus making it useful for similar mixed oxides preparations.