Page 137 - Synthesis of Functional Nanoparticles Using an Atmospheric Pressure Microplasma Process - LiangLiang Lin
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Rare Earth Doped Yttrium Oxide Nanophosphors Synthesis and Engineering- Controllable Photoluminescence Properties
 Figure 7.1 (a) Representative images of the microplasma reactor, plasma-liquid interaction process and the electrolyte solution after plasma treatment; (b) Optical emission spectrum recorded during the plasma-liquid interaction process, inset shows the fitting result of the rotation temperature; (c) A schematic graph of possible reaction pathways of the plasma-induced lanthanide doping process.
By taking the fabrication of Eu3+ doped yttria nanophosphors as an example, thermal gravimetric analysis was performed to investigate the thermal decomposition process of the obtained rare earth hydroxide compounds, as shown in Figure 7.2. The first endothermic peak appears in the range of 50-150 °C, relating to the evaporation of physical-bounded water from the hydroxides. The second endothermic peak situated at ~280 °C accompanied by a total mass loss of 11% (from 96% to 85%) indicates the removal of structural water from the hydroxides to form the oxyhydroxides as intermediates. The last endothermic peak is located at ~490 °C, with a weight loss of 9% derived from the TG curve (from 79% to 70%), suggesting the oxyhydroxides are furtherly decomposed to form oxides. No sharp peaks are observed in the DTG/DSC curves beyond 600 °C, inferring the sample doesn’t undergo significant changes after this temperature.
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