The Origin of Room–Temperature Ferromagnetism（RTFM）in CeO2 Nanoparticles

• Main Authors: YI-HSIN LU, 盧一心
• Other Authors: Shih-Yun Chen
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/14471862427829870077

碩士 === 國立臺灣科技大學 === 高分子系 === 98 === This research discussion under the room temperature the cerium dioxide (CeO2) nanometer branch grain of ferromagnetism origin, by thermal crack solution preparation cerium dioxide nano particles, CeO2 nano particles which obtains carries on the redox reaction under the different temperature and the atmosphere, causes particle size and the oxygen flaw density change the CeO2 nano particles, gauges magnetism and the crystallinity again, hoped that establishes the CeO2 nano particles particle size - ferromagnetism, and oxygen vacancy - ferromagnetism correlational. Demonstrated in the experimental result, makes the CeO2 particle size size and the dispersivity and the protecting agent by the thermal crack solution system (oil sour oil amine) the increase related, the oil sour oil amine recruitment is higher, the particle size is bigger, and the pellet dispersivity is better, and the oxidation reduction experimental result showed that along with heat treatment temperature increment, the CeO2pellet fill-out, under the reducing atmosphere (Ar+3%H2) the annealing sample, the saturated magnetic moment (Ms) increases along with the annealing temperature rise, under the oxidizing atmosphere (O2) and (Air) under the annealing sample, the saturated magnetic moment drops along with the temperature rise. The 500oC annealing's sample has the biggest Ms value under the air, compares with the XRD computation's particle size result, extrapolated that the warm solution preparation CeO2 has the quite many oxygen vacancies, but its magnetic variation is the particle size and the oxygen vacancy content also changes.