The Influence of Mechanical Activation of ZnO and SnO2 Powder Mixtures on the Obtaining of Zinc Stannate Ceramics
NАTASA S. NIKOLIC1, TATJANA V. SRECKOVIC2 and MOMCILO M. RISTIC3
1Institute of Technical Sciences of SASA, Knez-Mihailova 35/IV, Belgrade 11000,
2Center for Multidisciplinary Studies, University of Belgrade, Kneza Viseslava 1A, Belgrade 11000
3Serbian Academy of Sciences and Arts,
Knez-Mihailova 35, Belgrade 11000, Yugoslavia
E-mail: natali@itn.sanu.ac.yu
Pages: 167-172
Abstract
Zinc stannate ceramics has characteristic electrical properties widely used in fabrication of various types of sensors. It is well known that the properties of materials are mostly preparation-dependent and that the structure of ceramic sensor material should be porous. That is just one of the problems that has to be solved, along with the basic one - the obtaining of specific chemical compound, zinc stannate. The subject of this work is the influence of mechanical activation on solid state chemical reaction, e. g., the formation of porous zinc stannate ceramics during different thermal treatments of compact samples obtained from ZnO and SnO2 powder mixtures activated for various times. Mixture of ZnO and SnO2 powders (molar ratio 2 : 1) was ac-tivated by milling in a vibratory mill with a continual regime in air, for different time periods. The shrinkage behaviour of samples during heating was followed by sensitive dilatometer. X-ray powder diffraction analysis of activated powders and thermally treated samples and SEM analysis were also performed. The main conclusion of the performed analyses is that porous, fine-grained zinc stannate ceramics could be obtained for certain time of activation at much lower temperatures than the ones reported in the literature, with simultaneous acceleration of the chemical reaction.
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