doc. Ing. Klára Částková, Ph.D.
E-mail:   castkova@fme.vutbr.cz  Dept.:   Institute of Materials Science and Engineering Dept. of Ceramics and Polymers Position:   Deputy Head Room:   A4/118 Dept.:   Institute of Materials Science and Engineering Dept. of Ceramics and Polymers Position:   Associate Professor Room:   A4/118

Supervised courses:

• Colloid and Surface Chemistry (9KPC)
• Synthesis of Nonmetallic Materials (WCH)

Publications:

• ČÁSTKOVÁ, K.; MACA, K.; SEKANINOVÁ, J.; NEMČOVSKÝ, J.; CIHLÁŘ, J.:
  Electrospinning and thermal treatment of yttria doped zirconia fibres
  journal article in Web of Science
• CHAMRADOVÁ, I.; VOJTOVÁ, L.; ČÁSTKOVÁ, K.; DIVIŠ, P.; PETEREK, M.; JANČÁŘ, J.:
  The effect of hydroxyapatite particle size on viscoelastic properties and calcium release from a thermosensitive triblock copolymer, Springer Berlin Heidelberg
  journal article in Web of Science
• ČÁSTKOVÁ, K.; HADRABA, H.; MATOUŠEK, A.; ROUPCOVÁ, P.; CHLUP, Z.; NOVOTNÁ, L.; CIHLÁŘ, J.:
  Synthesis of Ca,Y-zirconia/hydroxyapatite nanoparticles and composites
  journal article in Web of Science
• ČÁSTKOVÁ, K.; MATOUŠEK, A.; BARTONÍČKOVÁ, E.; CIHLÁŘ, J.; VANÝSEK, P.; CIHLÁŘ, J.:
  Sintering of Ce, Sm, and Pr Oxide Nanorods, The American Chemical Society
  journal article in Web of Science
• ČÁSTKOVÁ, K.; MACA, K.; CIHLÁŘ, J.; HUGHES, H.; MATOUŠEK, A.; TOFEL, P.; BAI, Y.; BUTTON, T.:
  Chemical Synthesis, Sintering and Piezoelectric Properties of Ba0.85Ca0.15 Zr0.1Ti0.9O3 Lead-Free Ceramics
  journal article in Web of Science
• TRUNEC, M.; ČÁSTKOVÁ, K.; ROUPCOVÁ, P.:
  Effect of Phase Structure on Sintering Behavior of Zirconia Nanopowders, Wiley-Blackwell
  journal article in Web of Science
• MACA, K.; CIHLÁŘ, J.; ČÁSTKOVÁ, K.; ZMEŠKAL, O.; HADRABA, H.:
  Sintering of gadolinia-doped ceria prepared by mechanochemical synthesis, Elsevier Science
  journal article in Web of Science

List of publications at Portal BUT

Abstracts of most important papers:

• TRUNEC, M.; ČÁSTKOVÁ, K.; ROUPCOVÁ, P.:
  Effect of Phase Structure on Sintering Behavior of Zirconia Nanopowders, Wiley-Blackwell
  journal article in Web of Science
  Zirconia nanopowder compacts with comparable particle sizes and pore size distributions but different phase structures were prepared. The sintering behavior of monoclinic, tetragonal, and cubic zirconia nanopowders was directly compared. The densification and microstructural changes during sintering were investigated. The tetragonal and cubic nanopowders showed similar sintering behavior whereas the monoclinic nanopowder exhibited a more difficult densification and coarser microstructure compared to tetragonal and cubic powders. The differences in the densification of zirconia nanopowders resulted from significant differences in the microstructure evolution during sintering. The microstructural changes in nanopowder compacts during sintering were described and a correlation between microstructural changes and interfacial energies associated with different crystal structures was discussed.
• BARTONÍČKOVÁ, E.; ČÁSTKOVÁ, K.; CIHLÁŘ, J.:
  Synthesis of nanocrystalline bismuth oxide,
  Acta Metallurgica Slovaca, Vol.13, (2007), No.6, pp.252-255, ISSN 1335-1532, Hutnická fakulta technickej university v Košiciach
  journal article - other
  The synthesis way of bismuth oxide is one of the most important factors for final chemical and electrical properties that are appropriate for possible application in solid oxide fuel cells, oxygen sensors, varistors, catalysts and photo catalysts. The nanocrystalline bismuth oxide has been synthesized via the microwave-assisted hydrothermal method. The influence of microwave treatment on the reaction mechanism has been studied. A two step procedure was established.
• MACA, K.; CIHLÁŘ, J.; ČÁSTKOVÁ, K.; ZMEŠKAL, O.; HADRABA, H.:
  Sintering of gadolinia-doped ceria prepared by mechanochemical synthesis, Elsevier Science
  journal article in Web of Science
  Gadolinia-doped ceria (GDC) ceramics were prepared by mechanochemical synthesis of ceria and gadolinia (10mol.%) powders with subsequent uniaxial pressing and pressureless sintering. The mechanochemical synthesis was conducted in an attritor with different dispersion media: neutral (distilled water), basic (aqueous solution of ammonia), acidic (aqueous solution of propionic acid), and non-polar medium (xylene with stearic acid). The effect of suspension composition and attritor milling time on the sintering behaviour and ionic conductivity of GDC was studied. An attritor milling time of 3 to 6 hours was evaluated as the optimum milling time from the viewpoint of further sintering behaviour. Longer milling times resulted in nanometre-sized powders, whose sintering behaviour deteriorated due to powder agglomeration. The appearance of agglomerates in the non-polar medium was reduced. The ionic conductivity of the samples was evaluated by impedance spectroscopy and correlated with their microstructure.
• ČÁSTKOVÁ, K., HADRABA, H., CIHLÁŘ, J.:
  Hydrothermal ageing of tetragonal zirconia ceramics,
  Ceramics-Silikáty, Vol.48, (2004), No.3, pp.85-91, ISSN 0862-5468
  journal article - other
  The effect of hydrothermal treatment on the phase stability, microstructure and mechanical properties of tetragonal zirconia ceramics stabilized with 3 mol% yttria was studied. At temperatures of 140-260C the tetragonal phase transformed into monoclinic zirconia. The degree of transformation increased with increasing temperature and time of ageing. Changes in the microstructure and mechanical properties were observed for the samples used at temperatures of 180C and higher. The thickness of transformed layer increased with increasing temperature and at 260C it reached a thickness of 170 mikrom after 10 hours. The changes in mechanical properties (hardness and fracture toughness) corresponded to the structural changes in the material caused by hydrothermal ageing. Temperatures of 180C and higher were critical for the mechanical and structural properties of the material.
• CIHLÁŘ, J.; ČÁSTKOVÁ, K.:
  Direct synthesis of nanocrystalline hydroxyapatite by hydrothermal hydrolysis of alkylphosphates,
  Monatshefte fuer Chemie, Vol.133, (2002), No.6, pp.761-771, ISSN 0026-9247
  journal article - other
  The influence of reaction conditions (temperature, type of catalyst, time) on the base-catalyzed reaction of mono-, di-, and trialkylphosphates (alkyl=methyl, ethyl, i-propyl, n-butyl) with Ca2+ ions and on the structure and composition of the reaction products was studied. The composition of the calcium phosphates depends mainly on the reaction temperature. At temperatures below 100 degC, a nanocrystalline solid products transforming into dicalcium phosphate by heating (calcination) was found.Pure nanocrystalline hydroxyapatite was prepared by hydrothermal synthesis at 160 degC from mono- and dialkylphosphates. The size of hydroxyapatite crystallites was about 1 nm, the particle size about 150 um. Agglomerated particles of hydroxyapatite larger than 2 um were prepared at 200 degC. Hydrothermal reaction of trialkylphosphates with Ca2+ ions at 200 degC produced CaHPO4. The experimental results were used to propose a reaction mechanism for base-catalyzed hydrothermal reactions of alkylphosphates with Ca2+ ions.