Processing and dielectric properties of ZnTiO3 ceramics prepared from nanopowder synthesised by sol-gel technique
Résumé
ZnTiO3 nanopowders were obtained by sol-gel method. The nanopowders were characterised by means of TGA/DTA analysis, X-ray diffraction, TMA analysis and SEM characterisation. The results show that the crystalline structure of the sol-gel powders was obtained at 600°C, with crystallite sizes of 10 nm. SEM shows that most of the prepared ZnTiO3 nanopowders are agglomerated. Since agglomeration plays an important role in the sintering of the ZnTiO3 ceramics, different deagglomeration techniques (ultrasonication, pulverisation and attrition milling) were investigated. Dense ZnTiO3 structure was obtained from the attrition milled powder at 1050°C and its dielectric characteristics were also investigated (εr =25, tε= -26 ppm/°C and tgδ < 10-3 at 1 MHz). The low sintering temperature and the good dielectric properties show promise for the manufacture of multilayered capacitors with internal copper electrodes.