The Electronic and The Local Structure of Room-Temperature Ferromagnetic Nanocrystalline Y-doped CeO2
碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 101 === The Y-doped CeO2 nanocrystals were successfully prepared by precipitation from cerium(III) nitrate, EG and DI water, the doping level of Y ranges from 0 to 15 at%. The crystal structure and the particle size were characterized by the x-ray diffraction (XRD)....
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| Format: | Others |
| Language: | zh-TW |
| Published: |
2013
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| Online Access: | http://ndltd.ncl.edu.tw/handle/20009164375394669222 |
| Summary: | 碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 101 === The Y-doped CeO2 nanocrystals were successfully prepared by precipitation from cerium(III) nitrate, EG and DI water, the doping level of Y ranges from 0 to 15 at%. The crystal structure and the particle size were characterized by the x-ray diffraction (XRD). The room temperature ferromagnetism (RTFM) was revealed by superconducting quantum interference device magnetometer (SQUID). The orbital- and element-selective techniques, x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) spectroscopy were then utilized to investigate the magnetic property and electronic structure of these nanocrystals. These results suggested that two defect structure: Ce3+-Vo-Y3+ and Y3+-Vo-Y3+ were coexist on the system of Y-doped CeO2 nanocrystals. The magnetism is strongly related to the trivalent cerium and the oxygen vacancies of number and structure. Finally, the relationship to the RTFM, defect and magnetism of Y-doped CeO2 nanocrystals in present study can be described by the F-center exchange mechanism (FCE) and all analysis spectroscopy.
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