Journal of Materials Science

, Volume 49, Issue 13, pp 4636–4642 | Cite as

Enhancement of thermoelectric power in layered Bi2Sr2Co2−x Ir x O y single crystals



We report on the structural, electrical, and thermal transport properties of the single crystals of Bi2Sr2Co2−x Ir x O y (0 ≤ x ≤ 0.2). Large-sized (centimeter-level) and good-quality single crystals were grown by a modified flux method. The substitution of Ir ions for Co ones makes the in-plane resistivity ρ ab increase monotonically, whereas, the in-plane thermopower S ab initially increases and then decreases as x is larger than 0.1. Therefore, among all samples, the in-plane power factor P ab (=S ab 2 /ρ ab) of Bi2Sr2Co1.9Ir0.1O y would reach a maximum value of 116.4 μWm−1K−2 at 300 K and shows a significant improvement of about 20 % compared to that of the parent sample. Our results indicate that an appropriate doping of Ir ions at Co-sites may provide an effective way to enhance the thermoelectric performance of Bi2Sr2Co2O y system.


Electrical Transport Property Thermal Transport Property Spin State Transition CoO2 Layer Layered Cobaltite 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work is supported by the National Key Basic Research under Contract No. 2011CBA00111, and the National Nature Science Foundation of China under Contract No. 11174293, U1232140, 11174288, and 10904151, and the Scientific Research Foundation for the Returned Overseas Chinese Scholars.


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© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Key Laboratory of Materials Physics, Institute of Solid State PhysicsChinese Academy of SciencesHefeiPeople’s Republic of China
  2. 2.High Magnetic Field LaboratoryChinese Academy of SciencesHefeiPeople’s Republic of China
  3. 3.University of Science and Technology of ChinaHefeiPeople’s Republic of China

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