Relation between grain size and tube to wire crossover for manganite nanoparticle assembled nanostructures.

A. G. LEYVA; H.E.TROIANI; J.CURIALE; R.D.SANCHEZ; P. LEVY

PHYSICA B - CONDENSED MATTER

elsevier

Año: 2007 vol. 398 p. 344 - 347

0921-4526

Nanoparticles assembled into nanostructures (NAN) of manganese perovskite oxides for different compositions and diameters have been synthesized following a template-assisted method. We discuss the relationship among geometrical, structural and nanostructuralparameters observed when synthesizing LaMnO3, La0.66Sr0.33MnO3, La0.66Ca0.33MnO3 and La0.325Pr0.300Ca0.375MnO3 manganite based complex oxides. For all the studied compounds, the structures are composed of an assembly of small (some few tens of nanometers) grains. They form nanotubes above some threshold diameter of the template, and nanowires below it. Here we focus on the correlation between grain size and the diameter at which the tube to wire crossover occurs. The threshold for this tube to wall crossover seems todepend on the specific compound. We present evidence from TEM observations that allow a rationalization of several phenomena in the synthesis process.