Summary: | The purpose of this work was to study the possibility of creating Gd2O3-nanoparticles by spark generation. For this, the Palas GFG 1000 aerosol generator was used with much positive results. The potential possibilities to tune the physical properties of the nanoparticles by varying a set of experimental parameters during the fabrication process have been studied. This was investigated by comparing particles made by two different types of methods: wet chemistry (colloids), which was used in an earlier study, and an aerosol technique (aerosols), that was explored in this study. In this work, the production of 10, 20 and 40 nm particles with a high yield was obtained. Reducing the size even more proved to be troublesome. It was only possible to create a small amount of 5 nm sized particles. The reason for this is still not clear and will have to be further studied. One drawback with the fabrication procedure that was used for this work, the aerosol method, is that the amount of particles that was created is low compared to the amount of particles created by the earlier investigated modified polyol method. In the future this amount can be increased either by connecting several generators in parallel or by increasing the efficiency of the neutralizer. Description of the production and characterization of nanometer sized Gd2O3-particles constitute the main part of this work. Agglomerated particles was created by a vaporization/condensation-method and deposited onto silicon substrates for characterization. SEM studies were made in order to compare concentrations of produced particles made by the aerosol method and by the modified polyol method. For characterization, TEM investigations were made to study particle size, morphology and reshaping behavior before and after sintering was done. By using the results obtained in this work several new projects can be explored. This is very promising for future tries when a full characterization concerning spark gap-distance, gas flow and sintering temperature will be done.
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