THERMAL EVOLUTION OF THE MICROSTRUCTURE OF NANOSIZED LAFEO3 POWDERS FROM THE THERMAL-DECOMPOSITION OF A HETERONUCLEAR COMPLEX, LA[FE(CN)(6)]CENTER-DOT-5H(2)O

The thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)].5H (2)O, leads to the preparation of nanosized single-phase perovskite-ty pe LaFeO3 powders. The microstructural evolution of LaFeO3 with the te mperature has been studied by x-ray diffraction (XRD), Fourier transfo rm infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), a nd transmission electron microscopy (TEM). The product of the decompos ition at 500 degrees C consists of nanoporous grains which have the mo rphology of the complex, but diffracting as a monocrystal of LaFeO3. A t the higher temperatures, the nanosized particles start to separate f rom each other, still keeping the shape of the complex grains and form ing soft agglomerates. The formation of LaFeO3 from the complex at low temperatures is facilitated by the formation of an orthorhombic trans ition phase.