2005/01/31 by X. G. Luo, H. Li, X. H. Chen +6
Materials Science · Physics and Astronomy · #Annealing (glass) #Crystallite #Doping #Ferromagnetism #Magnetic and transport properties of perovskites and related materials #Metal #Oxygen #Oxygen deficiency #Oxygen transport #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Thermal conduction #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1021/cm0521471
published as Chem. Mater. 18(2006); 1029-1035 · 8 pages, 9 figures
openalex publication_date 2006/01/19 · arxiv created 2006/03/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Magnetic and transport properties of polycrystalline Gd 1 - x Sr x CoO 3 - δ ( x = 0.10−0.70) annealed under the oxygen pressure of 165 atm at 500 °C are systematically investigated. Cluster-glass behavior is observed in the low doping range, while a ferromagnetic transition occurs at the high doping level. Transport measurements indicate insulator-like behavior for the samples with x ≤ 0.30, an insulator−metal transition around x = 0.35, and metallic behavior for higher x samples. However, the large oxygen deficiency leads to a re-entrance of insulator-like state for the samples with x ≥ 0.60. The annealing procedure under the high oxygen pressure at high temperature can diminish the oxygen deficiency and leads to restoration of the metallic state. The small radius of the Gd 3+ ion results in less conduction and lower T c compared to those of La 1 - x Sr x CoO 3 and Nd 1 - x Sr x CoO 3 as a result of the large structural distortion and the stability of the low-spin state.