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Synthesis of ceramic powder materials in the presence of the ultrasound field
Kočicová, Pavla ; Bartoníčková, Eva (referee) ; Částková, Klára (advisor)
The thesis concerns the synthesis Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide. The theoretical part is focused on the characteristics, applications and possibilities of the Cerium Oxide synthesis. The experimental part describes the precipitation of the Cerium Oxide powder. The synthesis of the powders were proceeded in the normal conditions or in the presence of ultrasonic field. For the purposes of description of the ready powders the x-ray diffraction (XRD) and the raster electron microscopy (SEM) were used. The ceramics were made of the selected powders where the structure was described by SEM, the density by Archimedes´Method and the grain size by grid-line intersect method. Using the precipitation synthesis, the pure powders of Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide were prepared. The powder morphology was strongly involved by the pH level and by ageing time. The ultrasound was accelerating the ageing. At the values of pH > 11 the rodlike particles were created. The ageing time and the ultrasound supported the creation of the rodlike particles. The ceramics made of the powder with the presence of the rodlike morphology showed the density up to 97,14% of the theoretical density.
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Synthesis of bioceramic materials based on hydroxyapatite
Kočicová, Pavla ; Králová, Marcela (referee) ; Částková, Klára (advisor)
The thesis deals with the precipitation synthesis of nanoparticle hydroxyapatite with goal to study the influence of reaction conditions on the morphology of the particles. The theoretical part is focused on biomaterials, bioceramics and phosphates characterization. Further the work is focused on hydroxyapatite, its characteristics and possible synthesis in particular. The synthesis of hydroxyapatite precipitation is described in the experimental part. Syntheses were performed at a reaction temperature of 0-80 °C at pH = 8-11, at the aging time of 0-24 h, in the presence of surfactant and the chelating agent and with the post-precipitation hydrothermal or ultrasonic treatment. For characterization of the prepared powders, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), laser diffraction (LD) and the analysis of the specific surface area (BET) were used. Pure hydroxyapatite powders or a mixture of hydroxyapatite and tricalcium phosphate were prepared by precipitation syntheses. HA particle morphology was strongly affected by the reaction temperature – with increasing temperature the larger particles with a clearer morphology were formed, mostly in the rod shape. Postprecipitation hydrothermal treatment had a significant influence on the morphology of HA particles – it caused the formation of spherical or slightly elongated particles. The reaction medium of water/ethanol significantly affected the particle morphology – it inhibited the particle growth.
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Synthesis of bioceramic materials based on hydroxyapatite
Kočicová, Pavla ; Králová, Marcela (referee) ; Částková, Klára (advisor)
The thesis deals with the precipitation synthesis of nanoparticle hydroxyapatite with goal to study the influence of reaction conditions on the morphology of the particles. The theoretical part is focused on biomaterials, bioceramics and phosphates characterization. Further the work is focused on hydroxyapatite, its characteristics and possible synthesis in particular. The synthesis of hydroxyapatite precipitation is described in the experimental part. Syntheses were performed at a reaction temperature of 0-80 °C at pH = 8-11, at the aging time of 0-24 h, in the presence of surfactant and the chelating agent and with the post-precipitation hydrothermal or ultrasonic treatment. For characterization of the prepared powders, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), laser diffraction (LD) and the analysis of the specific surface area (BET) were used. Pure hydroxyapatite powders or a mixture of hydroxyapatite and tricalcium phosphate were prepared by precipitation syntheses. HA particle morphology was strongly affected by the reaction temperature – with increasing temperature the larger particles with a clearer morphology were formed, mostly in the rod shape. Postprecipitation hydrothermal treatment had a significant influence on the morphology of HA particles – it caused the formation of spherical or slightly elongated particles. The reaction medium of water/ethanol significantly affected the particle morphology – it inhibited the particle growth.
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Synthesis of ceramic powder materials in the presence of the ultrasound field
Kočicová, Pavla ; Bartoníčková, Eva (referee) ; Částková, Klára (advisor)
The thesis concerns the synthesis Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide. The theoretical part is focused on the characteristics, applications and possibilities of the Cerium Oxide synthesis. The experimental part describes the precipitation of the Cerium Oxide powder. The synthesis of the powders were proceeded in the normal conditions or in the presence of ultrasonic field. For the purposes of description of the ready powders the x-ray diffraction (XRD) and the raster electron microscopy (SEM) were used. The ceramics were made of the selected powders where the structure was described by SEM, the density by Archimedes´Method and the grain size by grid-line intersect method. Using the precipitation synthesis, the pure powders of Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide were prepared. The powder morphology was strongly involved by the pH level and by ageing time. The ultrasound was accelerating the ageing. At the values of pH > 11 the rodlike particles were created. The ageing time and the ultrasound supported the creation of the rodlike particles. The ceramics made of the powder with the presence of the rodlike morphology showed the density up to 97,14% of the theoretical density.
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