用溶胶-凝胶法制备La0.8Sr0.2Mn1-yFeyO3(y=0.10,0.12,0.14,0.16)样品,测试并分析该样品在2~18 GHz微波频率范围的复介电常数、复磁导率、损耗角正切及微波吸收系数与频率的关系,发现y=0.12,0.14时吸波的效果最好.样品厚度为2 mm、y为0.12时,有2个吸收峰,吸收峰值最高达22 dB,10 dB以上吸收频带宽度达6.2 GHz;厚度2.21 mm样品8 dB以上的吸收频宽达8.5 GHz.初步探讨了该材料的电磁损耗机理,电磁特性参数在频率为12.4 GHz位置发生阶跃式变化,在小于12.4 GHz频率范围以介电损耗为主,在大于12.4 GHz频率范围以磁损耗为主,这与Fe对Mn3+-O-Mn4+之间的影响有关.电导率测试表明在室温范围内电导在半导体范围内,有利于降低微波在氧化物表面的反射率.
参考文献
[1] | 戴道生;熊光成;吴思诚 .Re1-xTxMnO3氧化物的结构、电磁特性和巨磁电阻[J].物理学进展,1997,17(02):201-222. |
[2] | 胡季帆,梅良模,丁志强,付刚,赵文瑾,张清泉,刘宜华.钙钛矿氧化物La0.65(Ca,Ba)0.35Mn1-xFexOy的磁电阻效应[J].稀土,2000(01):19-22. |
[3] | 许恒毅,曹庆琪,唐涛,张世远.稀土锰氧化物La1-xNaxMnO3室温磁电阻效应研究[J].功能材料,2001(02):147-148. |
[4] | 尹荔松 .掺杂LaMnO<,3>体系的制备及其磁性和热性研究[D].中山大学,2003. |
[5] | Owens F J .DC Magnetic field dependent microwave absorption in CMR material La0.7 Sr0.3 Mn3[J].Physical and Chemistry of Solids,1997,58(09):1311-1314. |
[6] | Belevtsev BI.;Cherpak NT.;Chukanova IN.;Gubin AI.;Krasovitsky VB. Lavrinovich AA. .Magnetic inhomogeneity effects in DC transport properties and microwave absorption of La0.5Sr0.5CoO3-delta film[J].Physica, E. Low-dimensional systems & nanostructures,2003(1/3):304-305. |
[7] | 郭焕银,刘宁,徐素军,童伟,张裕恒.掺杂少量Sm时La0.67-xSmxSr0.33MnO3(0.00≤x≤0.30)的磁电性质[J].硅酸盐学报,2004(12):1481-1485,1495. |
[8] | 徐坚,熊惟皓,曾爱香,王采芳.稀土元素在磁性吸波材料中的应用研究进展[J].稀土,2004(06):68-73. |
[9] | Li G.;Hu GG.;Zhou HD.;Fan XJ.;Li XG. .Attractive microwave-absorbing properties of La1-xSrxMnO3 manganite powders[J].Materials Chemistry and Physics,2002(1/3):101-104. |
[10] | 胡国光,尹萍,吕庆荣.LaxSr1-xMnO3氧化物的导电和吸收特性[J].中国稀土学报,2002(02):179-181. |
[11] | Kagotani T;Fujiwara D;Sugimoto S.Enhancement of GHz electromagnetic wave absorption characteristics in aligned M-type barium ferrite Ba1-xLaxZnxFe12x-y(Me0.5 Mn0.5)yO19(x = 0.00-0.5; y=1.0-3.0,Me:Zr,Sn) by metal substitution[J].Journal of Magnetism and Magnetic Materials,2004(272-276):e1813-e1815. |
[12] | 吴晓光;车晔秋.国外微波吸收材料[M].长沙:国防科技大学出版社,1992 |
[13] | Ogale SB.;Bathe R.;Date SK.;Patil SI.;Hannoyer B.;Petit F.;Marest G.;Shreekala R. .Transport properties, magnetic ordering, and hyperfine interactions in Fe-doped La0.75Ca0.25MnO3: Localization-delocalization transition[J].Physical Review.B.Condensed Matter,1998(13):7841-7845. |
[14] | 李斌太,陈大明,陈钦生.铁氧体微波吸收材料的研究进展[J].硅酸盐通报,2004(05):66-69. |
[15] | Ahn K H;Wu X W;Liu K et al.Magnetic properties and colossal magnetoresistance of La (Ca) MnO3materials doped with Fe[J].Physical Review B,1996,54(21):15299-15302. |
[16] | Tkachuk A.;Brown DE.;Dabrowski B.;Fedro AJ.;Kimball CW. Pyles B.;Xiong X.;Rosenmann D.;Dunlap BD.;Rogacki K. .Dynamics of phase stability and magnetic order in magnetoresistive (La0.83Sr0.17Mn0.98Fe0.02O3)-Fe-57[J].Physical Review.B.Condensed Matter,1998(14):8509-8517. |
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