利用溶胶-凝胶(sol-gel)法制备出了一系列La0.8Sr0.2Co1-xFexO3样品.xRD结果显示,在La0.8Sr0.2Co1-xFexO3系列样品中,未掺杂的La0.8Sr0.2CoO3样品具有很好的单相结构,并且衍射峰没有发生劈裂;而Fe掺杂的La0.8Sr0.2CoO3样品中几乎每个衍射峰都发生了劈裂,在Fe掺杂的La0.8Sr0.2CoO3样品中可能存在两种不同的晶体结构.利用xANES研究了La0.8Sr0.2Co1-xFexO3样品中Co离子和Fe离子的化合价发现,Fe离子存在两种不同的化合价态,即Fe3+和Fe4+离子,在La0.8Sr0.2Co1-xFexO3样品中形成了两个不同离子的富集区,一个是由Co3+、Co4+和Fe3+等离子组成的,一个是由Fe4+和Co3+、Co4+等离子组成的,因此在Fe掺杂的La0.8Sr0.2CoO3样品中存在两种不同的晶体结构.
The polycrystalline samples of La0.8Sr0.2Co1-xFexO3 were prepared by the sol-gel method, xRD shows that in La0.8Sr0.2Co1-xFexO3 system the undoped La0.8Sr0.2CoO3 sample has a single phase, and the diffraction peaks do not split; but in Fe-doped La0.8Sr0.2CoO3 samples almost all of the diffraction peaks are splitted, implying that there are probably two different crystal structures in Fe-doped La0.8Sr0.2CoO3 samples. The results of xANES indicate that Fe ions have two differ-ent valences such as Fe3+ and Fe4+ ions in La0.8Sr0.2Co1-xFexO3 system. The results also reflect two different ions-rich areas in La0.8Sr0.2Co1-xFexO3samples: one includes Co3+, Co4+, Fe3+ ions, and another includes Co3+, Co4+, Fe4+ ions. Thus it induces two different crystal structures in Fe-doped La0.8Sr0.2CoO3 samples.
参考文献
| [1] | Manh-Huong Phan;The-Long Phan;Thanh-Nhan Huynh;Seong-Cho Yu;Jang Roh Rhee;Nguyen Van Khiem;Nguyen Xuan Phuc .Spin dynamics and spin-glass state in Fe-doped cobaltites[J].Journal of Applied Physics,2004(11):7531-7533. |
| [2] | A. Barman;M. Ghosh;S. Biswas .Giant magnetoresistance in La↓(0.8)Sr↓(0.2)Fe↓(x)Co↓(1-x)O↓(3)(0.025≤X≤0.3)[J].Applied physics letters,1997(21/24):3150-3152. |
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