Effect of Sr-Doping Concentration on Structure and Phase-Separation between Ferromagnetic and Paramagnetic Phases in Lanthanum Manganite Oxide
The perovskite La1-xSrxMnO3 (LSMO) nanocrystalline compounds with the doping concentration x in the range of 0.2~0.5 have been synthesized by combustion method using the pair of citric acid and ethylene glycol as a burning fuel.It was found that the sintering temperatures at which the compounds began forming the single-phase of LSMO increased from 900 ℃ up to 1200 ℃ corresponding to the increasing of Sr-doping content.X-ray pattern investigations presented the crystalline sizes of all samples sintered at 1200 ℃ evidently reduced from 77.7 nm to 18.9 nm as the doping concentration x increases.The effects of Sr-doping levels on Mn4+/Mn3+ ratio as well as on their electrical resistivity are also studied by X-ray photoelectron spectroscopy and four-point probes method,respectively.By using a resistive approximation model,the role of the Sr-doping with respect to the phase-separation between ferromagnetic and paramagnetic phases of these compounds is discussed.
combustion method lanthanum manganite oxide resistivity
Le Van Khoa Bao Guangze Tang Xinxin Ma
School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Key Lab on Materials Behavior & Evaluation Technology in Space Environment,Harbin Institute of Techn State Key Lab of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China
国际会议
桂林
英文
127-133
2012-07-16（万方平台首次上网日期，不代表论文的发表时间）