Micro- and Nanocomposites of Barium Zirconate Incorporated in Polymer Matrix

The radiation properties and the crystalline structure of hybrid composites based on polymer matrices—polystyrene, poly-3,4-ethylenedioxithiophene, polyphenylacetylene, polyvinyl alcohol and micro- (d < 10 µm) and nanocrystals (d < 50 nm) of BaZrO3 have been studied using luminescent spectroscopy, X-ray analysis and FTIR-spectroscopy. A strong cathodoluminescence in pristine BaZrO3 micro- and nanocrystal powders aneled at 500, 700, and 900 °C is observed in temperature range 80–293 K. Spectrum can be decomposed into three bands with maxima at E = 2.99, 2.69 and 2.2 eV. It was also found that composites of probed polymers (polyphenylacetylene, poly-3,4-ethylenedioxithiophene, and polyvinyl alcohol) do not produce sufficient effect on the luminescent spectra of nanocrystals. In the case of polystyrene–BaZrO3 composites, the cathodoluminescent spectrum is modified: both the low- and high-energy bands (near 4 eV) appear, together with a significant reduction in the cathodoluminescence intensity. A decrease of the lattice parameter “а” for BaZrO3 phase in the composite and the modification of cathodoluminescence spectra indicate changes in the nanocrystalline structure induced by the polymer. Interaction of BaZrO3 nanocrystals with polymer matrix was confirmed by FTIR spectroscopy.