(1-x).Pr0.67Ca0.33MnO3/x.Pr0.67Sr0.33MnO3 (x=0, 0.25, 0.50, 0.75 ve 1.0) Kompozit Malzemelerinin Yapısal, Morfolojik ve Elektriksel Özelliklerinin İncelenmesi

Abstract

Bu çalışmada sol-jel yöntemi kullanılarak hazırlanan (1-x).Pr0.67Ca0.33MnO3/x.Pr0.67Sr0.33MnO3 (x=0, 0.25, 0.50, 0.75 ve 1.0) kompozit malzemelerinin yapısal, morfolojik ve elektriksel özellikleri incelenmiştir. Ana ve kompozit malzemelerin x-ışınları kırınım (XRD) desenlerinden, kristal yapı simetrilerinde herhangi bir değişiklik meydana gelmediği gözlenmiştir. Kompozit malzemelerin ana pikinin, Pr0.67Ca0.33MnO3 ve Pr0.67Sr0.33MnO3 bileşiklerinin ana pikleri arasında optimize olduğu bulunmuştur. Atomik kuvvet mikroskobu çalışmalarından, bileşiklerin yüzeyindeki tane oluşumlarının aynı doğrultuda olduğu ve çok fazla farklılıkların olmadığı bulunmuştur. Taramalı elektron mikroskobu (SEM) çalışmaları Pr0.67Ca0.33MnO3 ve Pr0.67Sr0.33MnO3 bileşiklerinin yüzey morfolojilerinin birbirlerinden farklı olduğunu göstermiştir Elektriksek özdirenç ölçümlerinden, Pr0.67Ca0.33MnO3 bileşiğinin yarıiletken ve Pr0.67Sr0.33MnO3 bileşiğinin 199,1 K’in altında iletkenlik özellik gösterdiği ortaya çıkarılmıştır. Yarıiletken özellik gösteren Pr0.67Ca0.33MnO3 bileşiğine %25 oranında Pr0.67Sr0.33MnO3 bileşiği katıldığında elde edilen kompozit malzemenin, 88,4 K’in altında iletkenlik özellik kazandığı ve Pr0.67Sr0.33MnO3 fazının hacimsel oranının artması sonucunda TIM geçiş sıcaklığının yüksek sıcaklıklara doğru (184,8 K) kaydığı bulunmuştur.

Keywords

• Manyetokalorik etki
• X-ışınları kırınım
• Sol-jel yöntemi

Investigation of Structural, Morphological and Electrical Properties of (1-x).Pr0.67Ca0.33MnO3/x.Pr0.67Sr0.33MnO3 (x=0, 0.25, 0.50, 0.75 and 1.0) Composite Materials

Abstract

In this study, (1-x).Pr0.67Ca0.33MnO3/x.Pr0.67Sr0.33MnO3 (x=0, 0.25, 0.50, 0.75 and 1.0) composite materials were prepared using the sol-gel method and the structural, morphological, and electrical properties were investigated. From the x-ray diffraction (XRD) analysis, was observed that there was no change in the crystal structure symmetries of the pure and composite materials. It was found that the main peak of the composite materials changing between the main peaks of Pr0.67Ca0.33MnO3 and Pr0.67Sr0.33MnO3 compounds. From atomic force microscopy studies, it has been found that the grain formations on the surface of the compounds are in the same direction and there is not much difference between them. Scanning electron microscopy (SEM) studies have shown that the surface morphologies of Pr0.67Ca0.33MnO3 and Pr0.67Sr0.33MnO3 compounds differ from each other. From the electrical resistivity measurements, it was revealed that the Pr0.67Ca0.33MnO3 compound was a semiconductor and the Pr0.67Sr0.33MnO3 compound showed a conductivity behavior below 199.1 K. When 25% of the Pr0.67Sr0.33MnO3 compound is added to the Pr0.67Ca0.33MnO3 compound, which has semiconductor properties, the obtained composite material was gained conductivity below 88.4 K. As a result of the increase in the volumetric ratio of the Pr0.67Sr0.33MnO3 phase, the TIM transition temperature has shifted towards higher temperatures (184.8 K).

Keywords

• Magnetocaloric effect
• X-ray diffraction
• Sol-gel method

References

1. [1] T. Hashimoto, T. Numasawa, M. Shino, T. Okada, “Magnetic refrigeration in the temperature range from 10 K to room temperature: the ferromagnetic refrigerants,” Cryogenics, vol. 21, pp. 647-653, 1981.
2. [2] G. V. Brown, “Magnetic heat pumping near room temperature,” J. Appl. Phys., vol. 47, pp. 3673-3680, 1976.
3. [3] A. C. Hudgins, Jr. A.S. Pavlovic, “Magnetocaloric effect in dysprosium,” J. Appl. Phys, vol. 36, pp. 3628-3630, 1965.
4. [4] R. Szymczak, R. Kolano, A. Kolano-Burian, V.P. Dyakonov and H. Szymczak, “Giant magnetocaloric effect in manganites,” Acta Physica Polonica A, vol. 117, pp. 203-206, 2010.
5. [5] M. Quintero, J. Sacanell, L. Ghivelder, A. M. Gomes, A. G. Leyva and F. Parisi, “Magnetocaloric effect in manganites: metamagnetic transitions for magnetic refrigeration,” Appl. Phys. Lett. vol. 97, pp. 121916-121919, 2010.
6. [6] A. O. Ayas, M. Akyol, A. Ekicibil, “Structural and magnetic properties with large reversible magnetocaloric effect in (La1-xPrx)(0.85)Ag0.15MnO3 (0.0 < x < 0.5) compounds,” Philosophical Magazine, vol. 96, no.10, pp. 922-937, 2016.
7. [7] Y. Samancıoğlu, A. Coşkun, “Magnetic properties of A- and B-site cation doped La0.65Ca0.35MnO3 manganites,” Journal of Alloys and Compounds, vol. 507, no. 2, pp. 380-385, 2010.
8. [8] N. Dhahri, M. Abassi, E. K. Hlil and J. Dhahri, “Magnetocaloric effect in perovskite manganite La0.67−x Eu x Sr0.33MnO3,” Journal of Superconductivity and Novel Magnetism, vol. 28, pp. 2795–2799, 2015.

9. [9] M. Hsini, L. Ghivelder and F. Parisi, “Critical behavior investigated through magnetocaloric effect in PrSrMnO and Pr(Sr,Ca)MnO manganites,” Journal of Magnetism and Magnetic Materials, vol. 535, no. 1, pp. 168059-168067, 2021.
10. [10] A. Guedri, S. Mnefgui, S. Hcini, E.K. Hlil, A. Dhahri, “B-site substitution impact on structural and magnetocaloric behavior of La0.55Pr0.1Sr0.35Mn1-xTixO3 manganites,” Journal of Solid State Chemistry, vol. 297, pp. 122046-122057, 2021.
11. [11] I.Z. Al-Yahmadi, A.M. Gismelseed, F. Al Ma'Mari, A.D. Al-Rawas , S.H. Al-Harthi , A.Y. Yousif, H.M. Widatallah , M.E. Elzain , M.T.Z. Myint, “Structural, magnetic and magnetocaloric effect studies of Nd0.6Sr0.4AxMn1-xO3 (A=Co, Ni, Zn) perovskite manganites,” Journal of Alloys and Compounds, vol. 875, no.15, pp. 159977-159985, 2021.
12. [12] M. Pekała, K. Pekała, V. Drozd, J.-F. Fagnard, P. Vanderbemden, “Effect of nanocrystalline structure on magnetocaloric effect in manganite composites (1/3)La0.7Ca0.3MnO3/(2/3)La0.8Sr0.2MnO3,” Journal of Alloys and Compounds, vol. 629, pp. 98–104, 2015.
13. [13] A. El Boukili, O. Mounkachi, M. Hamedoun, P. Lachkar, E.K. Hlil, A. Benyoussef, M. Balli, H. Ez-Zahraouy, “A study of structural, magnetic and magnetocaloric properties of (1−x) La0.6Ca0.4MnO3/xMn2O3 composite materials,” Journal of Alloys and Compounds, vol. 859, pp. 158392-158401, 2021.
14. [14] P.Bisht, M. Arpit, G. Rabindra and N. Mahato, “Structural and magnetocaloric properties (0.75)La0.7Ca0.3MnO3/(0.25)La0.84Sr0.16MnO3 nanocomposite,” Physica B: Condensed Matter, vol. 619, no. 15, pp. 413215-413224, 2021.
15. [15] D. K. Baisnab, T. G. Kumary, A.T. Satya, A. Mani, J. Janaki, R. Nithya, L.S. Vaidhyanathan, M.P. Janawadkar, A. Bharathi, “Intricacies of strain and magnetic field induced charge order melting in Pr0.5Ca0.5MnO3 thin films,” Journal of Magnetism and Magnetic Materials, vol. 323, pp. 2823–2827, 2011. [16] A. K. Saw, G. Channagoudra, S. Hunagund, R. L. Hadimani and V. Dayal, “Study of transport, magnetic and magnetocaloric properties in Sr2+ substituted praseodymium manganite,” Mater. Res. Express, vol. 7, pp. 016105-016113, 2020.
16. [17] J.A. Collado, C. Frontera, J.L.Garcia-Munoz, C.Ritter,M. Brunelli, , M.A.G. Aranda, “Room temperature structural and microstructural study for the magneto-conducting La5/8-xPrx Ca3/8MnO3 (0 < x < 5/8) series,” Chemistry of Materials , vol. 15, pp. 167-174, 2003.
17. [18] W. Boujelben, M. Ellouze, A. Cheikhrouhou, C. Dubourdieu, J. Pierre, W.B. Yelon, Q. Cai, K. Shimizu, “Neutron diffraction, NMR and magneto-transport properties in the Pr0.7Sr0.3MnO3 perovskite manganite,” Physica Status Solidi, Sectio A: Applied Research, vol. 191, pp. 243-254, 2002.
18. [19] A. Coşkun, E. Taşarkuyu, A. E. Irmak, “High magnetic entropy change in La0.70Ca0.21Ag0.09MnO3 compound” Journal of Alloys and Compounds, vol. 669, pp. 217-223, 2016.
19. [20] S. Mukhopadhyay and I.Das, “Colossal enhancement of magnetoresistance in La0.67Sr0.33MnO3 / Pr0.67Ca0.33MnO3 multilayers: reproducing the phase-separation scenario,” EPL (Europhysics Letters), vol. 83, no. 2, pp. 27003-27008, 2008.
20. [21] J. Barratt, M. R. Lees, G. Balakrishnan, and D. Mc K. Paul, “Insulator–metal transitions in Pr0.7Ca0.3MnO3 induced by a magnetic field,” Appl. Phys. Lett. vol. 68, pp. 424-427, 1996.