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摻雜鈣鈦礦鈷氧化物的製備、表徵及其電磁性質

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摻雜鈣鈦礦鈷氧化物的製備、表徵及其電磁性質

摻雜鈣鈦礦鈷氧化物的製備、表徵及其電磁性質

[摘要]:採用溶膠-凝膠的方法制備了La0.75Sr0.25Co1-xFexO3 (x=0,0.1)多晶樣品,對樣品凝膠進行熱分析, 瞭解樣品在不同溫度下發生的物理、化學變化,通過室溫X射線衍射檢測樣品的單相性, 用NT-MDT型原子力顯微鏡對樣品的微觀形貌及顆粒度進行表徵; 用振動樣品磁強計以及標準4探針法對樣品進行了電磁效能的研究.結果表明鐵的'摻入晶格結構基本沒有發生變化,但摻鐵後體系電阻率增大,出現半導體-金屬的轉變,由於Fe的摻入,1方面,鐵離子替代鈷離子減小了Co3+/Co4+ 的比例,從而削弱了原有的Co-O-Co之間的雙交換作用形成的鐵磁有序,另1方面增強了由Co-O-Fe以及Fe-O-Fe之間的超交換作用形成的反鐵磁有序.而且發現材料磁性明顯下降,轉變溫度向低溫方向移動,系統在低溫下由自旋團簇玻璃態轉變為自旋玻璃態.
[關鍵詞]:2級相變,摻雜鈣鈦礦鈷氧化物,鐵磁有序,反鐵磁有序,自旋玻璃態

The study of synthesis ,characterization and magnetic and electric properties of doping perovskite cobalt oxide compound
 

[Abstract]: Used the sol - gelatin the method to prepare the La0.75Sr0.25Co1-xFexO3 (x=0,0.1) polytropism sample, carried on the thermal analysis to the sample gelatin, understood sample physics, chemical change which occurred under the different temperature, through room temperature X beam diffraction examination sample single-phase, carried on the attribute with the NT-MDT atomic force microscope to the sample microscopic appearance and the granularity; Moreover analyzes the material with the infrared spectroscope chemistry band structure; Have conducted the electromagnetism performance research with the vibration sample magnetometer as well as the standard four probe method to the sample. The result indicated the iron mixes in the lattice structure basically not to change, after but mixes the iron the system electronic resistivity to increase, appears the semiconductor - metal the transformation, because Fe blend, on the one hand, the hard ion substitution cobalt ion reduced the Co3+/Co4+ proportion, thus weakened the ferromagnetic order which between the original Co-O-Co double substitution forms, on the other hand strengthened over-delivers by between Co-O-Fe as well as Fe-O-Fe trades the counter-ferromagnetic order which the function forms. Moreover discovery material magnetism drops obviously, the transition temperature to the low temperature traverse, the system for spins the glass under the low temperature by the spinning group bunch of glass condition transformation condition.
[Keyword]: two-level phase change, the doping perovskite cobalt oxide compound, ferromagnetic order; anti-ferromagnetic order;  spin-glass phase.
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