Group members:
Miroslav Mašláň, Radek Zbořil, Libor Machala, Roman Kubínek, Milan Vůjtek, Jiří Tuček
Main Research Subjects:
• Synthesis of iron oxide-based nanopowders by thermally induced solid-state reactions of the suitable Fe-precursors in combination with the postprocessing (chemical, magnetic) separation of nanoparticles.
• Magnetic characterization of the nanostructures by Mössbauer spectroscopy measurements at low temperatures and in external magnetic fields, SQUID magnetization measurements.
• Structural and size-morphology characterization by XRD, TEM, SEM, AFM, QELS, BET measurement of the specific surface area.
• Possible applications of the inorganic nanomaterials in the fields of the magnetic glass ceramics, zeolite industry (improvement of the properties by the magnetic modification), catalysis, nanopigments and biomedicine (sorption-purification processes, dialysis, contrasts agents in MRI).
Selected Specific Equipment:
For the nanomaterial research, we use (directly in laboratories of Palacky University) mainly 57Fe Mössbauer spectroscopy, XRD, AFM, thermal analysis (TG/DTA), IR spectroscopy (including near-IR), elemental (C,H,N,S) analysis, NMR and QELS measurement of particle size distribution. Thanks to cooperation with foreign partners, we use vibrating sample magnetometer, SQUID magnetometer, Conversion Electron Mössbauer spectroscopy. The superior equipments located in Nanomaterial Research Center of Palacky University:
• There are mainly equipment allowing different Mössbauer experiments including room temperature, low temperature (closed He cycle: 15-300K) and high temperature (300-1200 K) measurements. The full-fledged Mössbauer lab disposes of MS measurements in back scattering geometry, MS with resonance detection and, primarily, by the external field MS equipment (Oxford Instruments, 1.5-300 K, up to 10 T!).
• The atomic force microscopy (AFM) measurements of the powdered samples are carried out in air and room temperature using the AFM Explorer microscope (ThermoMicroscopes, USA) in a non-contact mode with Si tips. The technique is commonly used for the study of particle morphology and particle size distribution (the distribution of the vertical dimensions).
• Using AFM and QELS method, the changes in particle size distribution during isochemical transformations of Fe2O3 polymorphs are monitored (the size distribution analysis range of 2-1000 nm).
Additional recent selected publications by group members:
• R. Zboril, M. Mashlan, L. Machala and P. Bezdicka: Iron(III) oxides formed during thermal conversion of rhombohedral iron(III) sulfate, in: Material Research in Atomic Scale by Mössbauer Spectroscopy, eds. M. Mashlan, M. Miglierini, P. Schaaf, Kluwer Academic Publishers, Dordrecht, 2003, pp 21-30.
• M. Mashlan, R. Zboril and K. Barcova: Mössbauer spectroscopy in studying the thermally induced oxidation processes in iron-bearing silicate minerals, in: Material Research in Atomic Scale by Mössbauer Spectroscopy, eds. M. Mashlan, M. Miglierini, P. Schaaf, Kluwer Academic Publishers, Dordrecht, 2003, pp 271-284.
• K. Barcova, M. Mashlan, R. Zboril, and P. Martinec: Mössbauer study of transformation mechanism of Fe cations in olivine after thermal treatments in air, Journal of Nuclear and Radioanalytical Chemistry 255, 529-533 (2003).
• M. Vujtek, R. Zboril, R. Kubinek and M. Mashlan: Ultrafine particles of iron(III) oxides by view of AFM - novel route for study of polymorphism in nano-world, in: Science, technology and education of microscopy: an overview, A. Mendez-Vilas (ed.), Formatex, Badajoz (Spain), 2003, pp 60-68.
• F. Kovanda, V. Balek, V. Dorničák, P. Martinec, M. Mašláň, L. Bílková, D. Koloušek, I.M. Bountsewa: Thermal Behaviour of SyntheticPyroaurite-Like Anionic Clay, Jourmal of Thermal Analysis and Calorimetry, 71, (2003) 727-737.
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