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 WJCMP  Vol.1 No.4 , November 2011
Physical-Properties of Oxygen-Deficient Co-Based Perovskites: Co(Sr1-xYx)O3–δ (0.05 ≤ x ≤ 0.4)
Abstract: In this work, the syntheses and characterization of oxygen deficient perovskite cobalt oxides prepared under ambient pressure conditions with different “x” in the Co(Sr1-xYx)O3–δ; 0.05 ≤ x ≤ 0.4 series are reported. The system studied in the present investigation undergoes structural phase transition at room temperature from cubic to tetragonal symmetry. The samples with x ≥ 0.2 show a tetragonal structure with I4/mmm space group, while the samples with 0.05 ≤ x ≤ 0.15 reveal cubic with pm3m group symmetry. Quite similar to Ho-substituted system [J. Appl. Phys. 103, 07B903 (2008)], the present Y-doped magnetization data clearly show the appearance of an enhanced ferromagnetic component at ~350 K for 0.15 ≤ x ≤ 0.225. Unlike the Ho-substituted system, the present narrow compositions behave as hard ferromagnet with quite high coercive field, Hc = 11.02, 12.25 and 14.0 kOe for x = 0.15, 0.2 and 0.225 compositions, respectively at T = 10 K. All the compositions show a semiconducting-like behaviour and some interesting features of temperature dependence of magnetoresistance (MR) are observed. The Co(Sr1-xYx)O3–δ samples seemly to obey variable range hopping conduction model showing a linear ln ρ versus T–1/4 dependence at the temperature range 80 K ≤ T ≤ 300 K.
Cite this paper: nullS. Balamurugan, "Physical-Properties of Oxygen-Deficient Co-Based Perovskites: Co(Sr1-xYx)O3–δ (0.05 ≤ x ≤ 0.4)," World Journal of Condensed Matter Physics, Vol. 1 No. 4, 2011, pp. 145-152. doi: 10.4236/wjcmp.2011.14021.
References

[1]   I. O. Troyanchuk, N. V. Kasper, D. D. Khalyavin, H. Szymc- zak, R. Szymczak and M. Baran, “Magnetic and Electri- cal Transport Properties of Orthocobaltites R0.5Ba0.5CoO3 (R = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy),” Physical Review B, Vol. 58, No. 5, 1998, pp. 2418-2421. doi:10.1103/PhysRevB.58.2418

[2]   R. L. Withers, M. James and D. J. Goossens, “Atomic Or- dering in the Doped Rare Earth Cobaltates Ln0.33Sr0.67 CoO3?δ (Ln = Y3+, Ho3+ and Dy3+),” Journal of Solid State Chemistry, Vol. 174, No. 1, 2003, pp. 198-208. doi:10.1016/S0022-4596(03)00227-5

[3]   S. Ya. Istomin, J. Grins, G. Svensson, O. A. Drozhzhin, V. L. Kozhevnikov, E. V. Antipov and J. P. Attfield, “Crys- tal Structure of the Novel Complex Cobalt Oxide Sr0.7 Y0.3CoO2.62,” Chemistry of Materials, Vol. 15, No. 21, 2003 pp. 4012-4020. doi:10.1021/cm034263e

[4]   M. James, D. Cassidy, K. F. Wilson, J. Horvat and R. L. Wi- thers, “Oxygen Vacancy Ordering and Magnetism in the Rare Earth Stabilised Perovskite Form of ‘SrCoO3?δ’,” Solid State Sciences, Vol. 6, No. 7, 2004, pp. 655-662. doi:10.1016/j.solidstatesciences.2003.03.001

[5]   S. Ya. Istomin, O. A. Drozhzhin, G. Svensson and E. V. Antipov, “Synthesis and Characterization of Sr1?xLnx CoO3?δ, Ln = Y, Sm-Tm, 0.1 x 0.5,” Solid State Sci- ences, Vol. 6, No. 6, 2004, pp. 539-546. doi:10.1016/j.solidstatesciences.2004.03.029

[6]   D. J. Goossens, K. F. Wilson, M. James, A. J. Studer and X. L. Wang, “Structural and Magnetic Properties of Y0.33 Sr0.67CoO2.79,” Physical Review B, Vol. 69, No. 13, 2004, pp. 134411(1-6).

[7]   W. Kobayashi, S. Ishiwata, I. Terasaki, M. Takano, I. Grigoraviciute, H. Yamauchi and M. Karppinen, “Room- Temperature Ferromagnetism in Sr1?xYxCoO3?δ (0.2 ≤ x ≤ 0.25),” Physical Review B, Vol. 72, No. 10, 2005, p. 104408. doi:10.1103/PhysRevB.72.104408

[8]   A. Maignan, S. Hébert, V. Caignaert, V. Pralong and D. Pelloquin, “Sr2/3Y1/3CoO8/3+δ: Transition from Insulating Antiferromagnet to Metallic Ferromagnet by Control of the Oxygen Content,” Journal of Solid State Chemistry, Vol. 178, No. 3, 2005, pp 868-873. doi:10.1016/j.jssc.2004.12.014

[9]   W. Kobayashi, S. Yoshida and I. Terasaki, “Unusual Im- purity Effect on Room Temperature Ferromagnet Sr3Y Co4O10.56,” Proceedings of International Conference on Perovskites-Properties and Potential Applications, Duben- dorf, 5-7 September 2005.

[10]   S. Fukushima, T. Sato, D. Akahoshi and H. Kuwahara, “Comparative Study of Ordered and Disordered Y1?xSrx CoO3?δ,” Journal of Applied Physics, Vol. 103, No. 7, 2008, pp. 07F705(1-3).

[11]   S. Kimura, Y. Maeda, T. Kashiwagi, H. Yamaguchi, M. Hagiwara, S. Yoshida, I. Terasaki and K. Kindo, “Field- induced Spin-State Transition in the Perovskite Cobalt Oxide Sr1?xYxCoO3?δ,” Physical Review B, Vol. 78, No. 18, 2008, pp. 180403(R)(1-4).

[12]   S. Balamurugan and E. Takayama-Muromachi, “Structu- ral and Magnetic Properties of High-Pressure/High-Tem- perature Synthesized (Sr1–xRx)CoO3 (R = Y and Ho) Pe- rovskites,” Journal of Solid State Chemistry, Vol. 179, No. 7, 2006, pp. 2231-2236.

[13]   V. Petricek, M. Dusek and L. Palatinus, “JANA2006, The Crystallographic Computing System,” Institute of Physics, Praha, 2006.

[14]   M. James, D. Cassidy, D. J. Goossens and R. L. Withers, “The Phase Diagram and Tetragonal Superstructures of the Rare Earth Cobaltate Phases Ln1?xSrxCoO3–δ (Ln = La3+, Pr3+, Nd3+, Sm3+, Gd3+, Y3+, Ho3+, Dy3+, Er3+, Tm3+ and Yb3+),” Journal of Solid State Chemistry, Vol. 177, No. 6, 2004, pp. 1886-1895. doi:10.1016/j.jssc.2004.01.012

[15]   S. Balamurugan, K. Yamaura, A. Asthana, A. Ubaldini, Y. Matsui, and E. Takayama-Muromachi, “Magnetic and Transport and Structure Properties of the Room Tem- perature Ferromagneto Sr1?xHoxCoO3?δ,” Journal of Ap- plied Physics, Vol. 103, No. 7, 2008, pp. 07B903(1-3).

 
 
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