arXiv subjects

Adeilton Pereira Maciel

Publications and source records attributed to Adeilton Pereira Maciel.

3 recordsLinked to original sources

arXiv2013

Synthesis and structural ordering of nano-sized Ba3B'Nb2O9 (B'= Ca and Zn) powders

In this work we investigated the phase formation and structural ordering of Ba$_{3}$B$^{'}$Nb$_{2}$O$_{9}$ (B$^{'}$ $=$ Ca and Zn) perovskite powders obtained by a modified polymeric precursor route using X-ray powder diffraction and Raman spectroscopy. We obtained single phase complex perovskites at 900 $^o$C. Williamson-Hall analysis and scanning electron microscopy showed that the powders have crystallites and particles of nanometric size.

cond-mat.mtrl-sci↗

arXiv2013

Ordering and phonons in Ba$_3$CaNb$_{2}$O$_9$ complex perovskite

In this work we performed a detailed investigation about ordering in \bcn perovskite. The sintering temperature and time were changed to obtain samples with different ordering. The order parameters were probed by Raman spectroscopy based on a partial disordered model. To use the partial disordered model correctly we performed {\it ab initio} calculations in \bcn to assign the optical phonons. The results showed that sintering temperature improves order while sintering time is not so efficient to promote order.

cond-mat.mtrl-sci↗

arXiv2012

Ba(Zn1/3Nb2/3)O3 thin films obtained by polymeric precursors method

In this work Ba(Zn1/3Nb2/3)O3_3$ thin films were prepared by the polymeric precursors method. A detailed description of the procedure to obtain the precursors and deposition was presented. High quality polycrystalline films of Ba(Zn1/3Nb2/3)O3 were obtained from Pt/Ti/SiO$_2$/Si substrate deposited by spin coating technique. X ray measurements show that the film crystallizes in a partial ordered trigonal structure characteristic of the 1:2 complex perovskites. The partial order and structure was confirmed by Raman measurements. Also, confocal Raman and atomic force microscopy was used to characterize the film morphology.

cond-mat.mtrl-sci↗