摘要
利用溶胶-凝胶法成功制备了BiFeO3和Bi0.95Eu0.05FeO3粉末样品,并讨论了温度和Bi离子的含量对样品制备的影响。铁电性和磁性测量显示:与BiFeO3样品相比,稀土(Eu)离子掺杂的BiFeO3样品的磁性和铁电性有很大提高。Raman谱数据分析得出,Eu离子掺杂引起了BiFeO3样品的局域结构的改变。Eu离子掺杂促使BiFeO3样品的磁性提高归因于局域结构改变导致了BiFeO3样品中的自旋轮摆结构的破坏,最终使样品的磁性提高。
BiFeO3 and Bi0.95 Eu0.05 FeO3 powders were successfully prepared by a sol-gel method.Effect of temperature and the amount of Bi ions on sample preparation was investigated.It was found that the magnetic and ferroelectric properties of Eu-doped BiFeO3 sample improve significantly with respect to pure BiFeO3 through ferroelectric and magnetic measurements.The data analysis of Raman spectra showed that Eu ion doping causes changes in the local structure of the BiFeO3 sample.The increase of BiFeO3 sample′s magnetism through Eu ion doping can be attributed to the destruction of spinning wheel pendulum structure caused by local structural change in the BiFeO3 samples.
引文
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