화학공학소재연구정보센터
Materials Science Forum, Vol.517, 45-48, 2006
Effect of Ru substitution on structural, electrical transport and magnetoresistive of La2/3Ba1/3MnO3
Polycrystalline samples of La0.67Ba0.33(Mn1-xRux)O-3 with x = 0, 0.05, 0.1, 0.15 and 0.2 have been prepared using solid state reaction. The effects of doping of Ru at Mn site on La-Ba-Mn-O ceramics, the characteristics and magnetotransport properties of CMR materials are investigated. The magnetoresistance (MR) effect is measured using the four point probe technique. The magnetoresistance defined as MR% = (R-o - R-H)/R-H X 100% was measured at a magnetic field of H <= 1T at 90K, 100K, 150K, 200K, 250K, 270K and 300K for the sample of doping x = 0, 0.05, 0.1, 0.15 and 0.2. Overall, MR drops slowly when temperature rises. All doping concentration gives small variation range (similar to 2.7% to similar to 26.78%). The electrical property has determined by using standard four-point probe resistivity measurement in a temperature range of 30 K to 300 K. Metalinsulator transition temperature (T-p) shifted to lower temperatures as Ru. doping is increased. In this paper the structural pattern and microstructure property have investigated via XRD. XRD patterns show that these systems are in orthorhombic distorted perovskite structures.