بررسی اثر اندازه‌ی ذرات بر خواص ساختاری و مغناطیسی منگنایت La0.6 Sr0.4MnO3

رئوفی, تینا; احسانی, محمدحسین; ثانوی خشنود, داود

بررسی اثر اندازه‌ی ذرات بر خواص ساختاری و مغناطیسی منگنایت La0.6 Sr0.4MnO3

نویسندگان

دانشگاه سمنان

چکیده

در این پژوهش، نمونههایی از ترکیب منگنایت La0.6 Sr0.4 MnO3 با روش سل-ژل و حالت جامد در ابعاد نانو و میکرومتری ساخته شدهاند. تحلیل ساختاری نمونهها با استفاده از دادههای بدست آمده از طیف پرتو ایکس (XRD) و نرمافزار فول پروف نشان داد که نمونهها در فاز رومبوهدرال با گروه فضایی R-3Cبلوری شدهاند. بررسی ویژگیهای مغناطیسی نشان داد که این ماده جزء دسته مواد فرومغناطیس نرم بوده و با کاهش اندازهی ذرات، دمای کوری نمونهها به صورت جزئی به دماهای پایینتر جابهجا میشود. محاسبهی گشتاور مغناطیسی موثر نمونهها از طریق مدل کوری-ویس نشان داد که با کاهش اندازهی ذرات، گشتاور مغناطیسی نمونهها کاهش مییابد. با اندازهگیری مغناطش بر حسب میدان، کاهش مغناطش اشباع در اثر کاهش اندازهی ذرات مشاهده شد. رفتار مشاهده شده بر اساس مدل مغزه-پوسته توصیف و ضخامت لایهی مردهی مغناطیسی برای نمونه نانومتری براورد شد.

کلیدواژه‌ها

20.1001.1.17263689.1395.24.4.6.4

عنوان مقاله [English]

Investigation of particle size effect on structural and magnetic properties of La0.6 Sr0.4 MnO3 manganite

چکیده [English]

In this work, La0.6Sr0.4MnO3 manganite particles with nano and micro scales were prepared by Sol-gel and solid state reaction methods. The results from X-ray diffraction analysis by Fullprof software showed that the samples have been crystallized in the rhombohedral structure with (R-3C) space group. Investigation of magnetic properties showed that this compound belong to soft ferromagnetic materials and Curie temperature of the samples shifted to lower temperatures with particle size reduction. Calculation of the effective magnetic moment using Curie-Weiss model showed the magnetic moment reduction of the samples with particle size decreasing. Using magnetization versus field, magnetic saturation reduction, due to particle size decreasing, was observed. The observed behavior described with Core-shell model and the thickness of magnetic dead layer was estimated.

کلیدواژه‌ها [English]

Particle size effect
Magnetic susceptibility
Core shell mode
La0.6Sr0.4MnO3 manganite

مراجع

[1] Tokyra Y., "Colossal magnetoresistive oxide", Department of Applied Physics University of Tokyo Japan (1999).

[2] Sujoy R., Lgor D., Dossah D. E., "Size induced variation in structural and magnetic properties of double exchange La0.8Sr0.2MnO3-δ nano-ferromagnet", Journul of Applied. Physics 96 (2004) 1202-1208.

[3] Ehsani M. H., Kameli P., Razavi F. S., Ghazi M. E., "Influence of Sm-doping on the structural, magnetic, and electrical properties of La0.8-xSmxSr0.2MnO3 ( 0< x < 0.45 ) mangenites", Journul of Alloys Compound 576 (2013) 406-414.

[4] Nedelko N., Lewinska S., Pashchenko A., "Magnetic properties and magnetocaloric effect in La0.7Sr0.3-xBixMnO3 mangenites", Journul of Alloys. Compound. 640 (2015) 433-439.

[5] Zheng G. H., Sun X. B., "Structure ,magnetic , and transport properties of the Co-doped manganites La0.9Te0.1Mn1-xCoxO3(0<x<0.25) ", Journal of Solid State Communication 137 (2006) 326-331.

[6] Tang W., Lu W. J., "Size-induced change of structural, magnetic and magnetocaloric properties of La0.7Ca0.2Ba0.1MnO3", Journal of Physica B 405 (2010) 2733-2741.

[7] Curiale J., Granada M., Troiani H. E., "Magnetic and layer in ferromagnetic nanoparticles", Journal of Applied. Physics Letters 95 (2009) 043106-1 – 043106-3.

[8] Wang J., Monivannan A., Wu N., "Sol-gel derived La0.6Sr0.4CoO3 nanoparticles, nanotubes, nanowires and thin films", Journal of Thin solid films 517 (2008) 582-587.

[9] Manh D. H., Phong P. T., "Size effects and interactions in La0.7Ca0.3MnO3nanoparticles", Journal of Alloys. Compound 509 (2011) 1373-1377.

[10] Mazaheri M., Akhavan M., "Perpetration and characterization of nano-polycrystalline lanthanum-based manganite La1-yKyCa0.3MnO3", Journal of Physica B 405 (2010) 72-76.

[11] Ritter C., Mahendiran R., Ibarra M. R., Rareau B., Rao C. N. R., "Direct evidence of phase segregation and magnetic-field-induced structural transition in Nd0.5Sr0.5MnO3 by neutron diffraction", Journal of Physical Review B, 61 (2001) R9229-9232.

[12] Mollah S., Huang H. L., Yang H. D., Pal S., Taran S., Chaudhuri Brect K., “hopping conduction in Pr0.65Ca0.35-xSrxMnO3 perovskites above the metal-insulator transition temperature”, Journal of Magnetism and Magnetic Materials 284(2004) 383-394.

[13] Liao D. Q., Sun Y., Yang R. F., Cheng Z. H., "Structural, magnetic, and electrical properties of La1-xNdxMn0.8Cr0.2O3(x≤0.3)", Physica B 394 (2007) 104-110.

[14] Batlle X., Labarta J., "Finite-size effects in fine particles: magnetic and transport properties", Journal of Applied. Physics 35 (2002) R15-42.

[15] Binder K., Hohenbry P. C., "Surface effects on magnetic phase transitions", Journal of Physical Review B 9 (1974) 2194-2214.

[16] Guimaraes A. P., "Principle of Nanomagnetism", Springer, 2009.

[17] Dong S., Gao F., Wang Z. Q., Liu J. M., "Surface phase separation in nano sized charge-ordered manganites", Journal of Applied. Physics. Letters 90 (2007) 082508-1 – 082508-3.

[18] Ehsani M. H., Kameli P., Ghazi M. E., Razavi F. S., "An investigation on magnetic interacting La0.6Sr0.4MnO3 nanoparticles", Journal of Advanced Materials Research 829 (2014) 712-716.

[19] Ehsani M. H., Kameli P., Ghazi M. E., Razavi F. S., Taheri M., "Tunable magnetic and magnetocaloric properties of La0.6Sr0.4MnO3 nanoparticles", Journal of Applied Physics 114 (2013) 223907-1 – 223907-9.

[20] Sarkar T., Ghosh B., Raychaudhuri A. K., "Crystal structure and physical properties of half-doped manganite nanocrystales of less than 100-nm size", Journal of Physical Review B 77 (2008) 235112.

[21] Muthuselvam I. P., Bhowmik R. N., "Grain size dependent magnetization, electrical resistivity and magnetoresistance in mechanically milled La0.67Sr0.33MnO3", Journal of Alloys and Compound , 511 (2012) 22-30.

[22] Ramakrishna P.V., Murthy D.B.R.K., Sastry D.L., Samatha K., "Synthesis, structural and luminescence properties of Mn doped ZnO/Zn2SiO4 composite microphospher", Spectrochimico Acta Part A: Molecular and Bimolecular Spectroscopy, 129 (2014) 274-279.

[23] Mokoma P.P., Gohain M., Bezuidenhoudt B.C.B., Swart H.C., Ntwaeaborwa O.M., "Luminescent properties and particle morphology of Ca3(Po4)2: Gd3+, Pr3+ phosphor powder prepared by microwave assisted synthesis", Journal of Luminescence 155 (2014) 288-292.

[24] Venkataiah G., Krishna D. C., "Effect of sintering temperature on electrical transport properties of La0.67Ca0.33MnO3", Journal of Physica 357(2005) 370-379.

[25] Lu W. J., Luo X., Hao C. Y., Song W H., "Magnetocaloric effect and Griffiths-like phase in La0.67Sr0.33MnO3 nanoparticles", Journal of Applied Physics 104 (2008) 113908-1 – 113908-5.

[26] Shaobo X. I., Wenjian L. u., "Magnetic properties and magnetocaloric effect of La0.8Ca0.2MnO3 nanoparticles tuned by particle size", Journal of Applied Physics 111 (2012) 063922-1 – 063922-9.

[27] Manh D. H., Phong P. T., "Size effects and interaction in La0.7Ca0.3MnO3 nanoparticles", Journal of Alloys and Compound 509 (2011) 1373-1377.

[28] Coey J M., Magn.Mag.Mat.Combridge University Press (2010) P:77.

[29] Tang W., Lu W.J., Lu X., Wang B.S., Zhu X.B., Song W.H., Yang Z.R., Sun Y.P., "Size-induced changes of structural, magnetic and magnetocaloric properties of La0.7Ca0.2Ba0.1MnO3", Journal of Physical B 405 (2010) 2733-2741.

[30] Dyakonov V., Slawska-Waniewska A., Piotrowski N., "Magnetic, resonance and transport properties of nanopowder of La0.7Sr0.3MnO3 manganites", Journal of Magnetism and Magnetic Materials 322 (2010) 3072-3079.

[31] Markovic D., Kusigerski M., Tadic M., "The influence of the heat treatment on the structural and magnetic properties of nanoparticle La0.7Ca0.3MnO3 prepared by glycine–nitrate method", Journal of Alloys and Compound 494 (2010) 52-57.