Li3xLa2/3−xTiO3 nanoparticles with different morphologies and self-organization, obtained from simple solution precipitation methods

We present a novel synthesis strategy of Li3xLa2/3−xTiO3 (LLTO) softly agglomerated nanoparticles by simple precipitation from solution and based on controlling the fractal self-organization. In this way we avoid the use of bulky organic ligands frequently used to avoid the irreversible aggregation of nanoparticles but that also often degrade the LLTO functional properties. We show that the pH of precipitation of titanium and lanthanum hydroxides (LLTO precursors) strongly affects the so-called “filtration coefficient” and the hierarchic structure of LLTO precursors (mass or surface fractal self-organization). For mass-fractal aggregation of the precursors, a high filtration coefficient was obtained with soft and readily friable aggregates of the hydroxide precipitates. Moreover, the fractal self-organization of the synthesized precursors strongly modifies the final LLTO nanoparticles morphology and the material connectivity. The LLTO nanoparticles synthesized from mass-fractal agglomerated precursors obtained from the so-called sequential precipitation of hydroxides (SPH, prepared at pHTi(OH)4=3.5 and pHLa(OH)3=8.5) had a much lower agglomeration ability than the surface-fractal agglomerated precursors obtained from the so-called co-precipitation of hydroxides (CPH, at pHTi(OH)4=pHLa(OH)3=8.5).