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【期刊论文】Structure and enhancement of negative thermal expansion in the PbTiO3–CdTiO3 system
陈骏, J. Chen, X. R. Xing, R. B. Yu, and G. R. Liu
APPLIED PHYSICS LETTERS 87, 231915 (2005),-0001,():
-1年11月30日
The structures of Pb1−xCdxTiO3 (x=0.03 and 0.06) were investigated by the x-ray Rietveld method at room temperature. It is surprising to find that the spontaneous polarization displacements of Pb/Cd and Ti atoms according to the oxygen polyhedron decrease, although the c/a ratio increases with doping-cadmium content. Cadmium substitution plays a unique role of enhancement of the negative thermal expansion in PbTiO3. The average bulk thermal expansion coefficient decreases from ā=−1.99×10−5 / °C for pure PbTiO3 to ā=−2.40×10−5 / °C for Pb0.94Cd0.06TiO3. The negative thermal expansion of PbTiO3 might be a consequence of hybridization between Pb and O atoms.
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【期刊论文】Structure and negative thermal expansion in the PbTiO3–BiFeO3 system
陈骏, J. Chen, X. R. Xing, G. R. Liu, J. H. Li and Y. T. Liu
APPLIED PHYSICS LETTERS 89, 101914 (2006),-0001,():
-1年11月30日
The structures of (1−x) PbTiO3–xBiFeO3 (x=0.3 and 0.6) were investigated by means of the neutron powder diffraction. A splitting shift between Fe and Ti atoms was found along the c axis in 0.7PbTiO3–0.3BiFeO3; however, this splitting does not appear in 0.4PbTiO3–0.6BiFeO3. The tetragonal phase of PbTiO3–BiFeO3 exhibits a large spontaneous polarization. The negative thermal expansion of PbTiO3 is significantly enhanced in a wide temperature range by the BiFeO3 substitution. The average bulk thermal expansion coefficient of 0.4PbTiO3–0.6BiFeO3 is ā v =−3.92×10−5 °C−1, which is much strong in the known negative thermal expansion oxides.
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【期刊论文】Thermal Expansion Properties of Lanthanum-Substituted Lead Titanate Ceramics
陈骏, Jun Chen, Xianran Xing, Ranbo Yu, and Guirong Liu
J. Am. Ceram. Soc., 88 [5] 1356–1358 (2005) ,-0001,():
-1年11月30日
The Pb1-xLaxTiO3 powders were prepared by a sol-gel route in the composition range from x=0.0 to 0.3 in 0.05 increments. The lattice parameters of Pb1-xLaxTiO3 (x=0.0, 0.05, 0.10, 0.15, 0.20, 0.30) were determined by a high temperature X-ray diffraction, and the intrinsic thermal expansion coefficients were obtained in the temperature range from room temperature to 9001C. The Pb1-xLaxTiO3 compounds (x=0.10, 0.15, 0.20) in the tetragonal system exhibit low thermal expansion behaviors. As the La content is increased, the phase transition in the Pb1-xLaxTiO3 changes continuously from conventional to diffuse phase transition
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【期刊论文】Thermal expansions of ceramics in the system Pb1−x(La1/2K1/2)xTiO3
陈骏, Jun Chen, Xianran Xing, Jinxia Deng, Guirong Liu
Journal of Alloys and Compounds 372 (2004) 259–266,-0001,():
-1年11月30日
The solid solution limit of Pb1−x(La1/2K1/2)xTiO3 was determined in the composition range of 0 ≤ x < 1. The compounds of Pb1−x(La1/2K1/2)xTiO3 were indexed in a tetragonal system for 0 ≤ x ≤ 0.4 and indexed in a cubic one for 0.45 ≤ x < 1 at room temperature. A tiny amount of La2Ti2O7 pyrochlore phase was detected in the sample Pb1−x(La1/2K1/2)xTiO3 for x = 1.0. The lattice parameters of Pb1−x(La1/2K1/2)xTiO3 (x = 0.1, 0.2, 0.3, 0.4, 0.6, 0.8) were determined by high temperature XRD, and their intrinsic thermal expansion coefficients were obtained in the temperature range from room temperature to 900 ◦C. In the temperature range from room temperature to the Curie point, the compound Pb0.8(La1/2K1/2)0.2TiO3 has a low intrinsic thermal expansion coefficient (−7.1×10−6 ◦C−1), which is the value closest to zero in all the investigated compounds. The (ferroelectric) Curie temperatures of Pb1−x(La1/2K1/2)xTiO3 could be predicted from our experimental results for 0≤x≤0.4.
Solid solution Pb1−x(, La1/, 2K1/, 2), xTiO3, Phase transition, High temperature X-ray powder diffractometry (, HTXRPD), , Thermal expansion, Curie temperature
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【期刊论文】Zero Thermal Expansion in PbTiO3-Based Perovskites
陈骏, Jun Chen, Xianran Xing, Ce Sun, Penghao Hu, Ranbo Yu, Xiaowei Wang, and Lihong Li
American Chemical Society,-0001,():
-1年11月30日
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