采用固相烧结工艺制备了Nb5+掺杂的Bi4Ti3O12层状结构铁电陶瓷.运用XRD 和AFM对Bi4Ti3-xNbxO12+x/2材料的微观结构进行表征,发现所制备的陶瓷均具有单一的正交相结构,抛光热腐蚀表面晶粒的显微形貌表现为随机排列的棒状结构.通过对材料直流电导率与温度关系的Arrhenius拟合,分析丁Bi4Ti3-xNbxO12+x/2的导电机理. Nb5+掺杂提高了材料的介电常数,但居里温度随掺杂含量的增加呈线性下降趋势.DSC结果显示Bi4Ti3-xNbxO12+x/2材料在居里温度处经历了一级铁电相变.样品的铁电性能测试结果表明, Nb5+掺杂Bi4Ti3O12提高了材料的剩余极化Pr,这主要是由于Nb5+取代Ti4+大大降低了材料中氧空位的浓度,使得氧空位对畴的钉扎作用减弱的缘故.
Nb5+-doped Bi4Ti3O12 layer-structured ferroelectric ceramics were prepared by the solid-state reaction technology. Microstructures of Bi4Ti3-xNbxO12+x/2 materials were characterized by XRD and SEM. The results show that Bi4Ti3-xNbxO12+x/2 material has a single orthorhombic structure. The grains of polished and thermally etched surfaces reveal a needle-like structure. Electronic conductor mechanism of Bi4Ti3-xNbxO12+x/2 was analyzed by the Arrhe-nius fit of direct current conductivity vs temperature. Dielect constants of Bi4Ti3-xNbxO12+x/2 ceramics increase by Nb5+ doping. The Curie temperatures decrease linearly with the increase of Nb5+ concedntration. DSC results show that Bi4Ti3-xNbxO12+x/2 materials undergo the firstorder ferroelectric phase transition at the Curie point. Nb5+ doping Bi4Ti3O12 ceramics results in an increase remanent polarizatgion (Pr) according to ferroelectric test results. The reason is that Nb5+ substituting for Ti4+ decreases the concentration of oxygen vacancies. The effect of oxygen vacancies on domain pinning is reduced significantly.
参考文献
| [1] | Hase T, Noguchi T, Takemura K, et al. Jpn. J. Appl. Phys., 1998, 37: 5198-5202. [2] Megriche A, Lebrun L, Troccaz M. Sensors and Actuators, 1999, 78: 88-91. [3] Aurivillius B. Ark. Kem., 1949, 1: 463-480. [4] Zheng L Y, Li G R, Zhang W Z, et al. Mater. Sci. Eng., 2003, B99: 363-365. [5] 晏海学, 李承恩, 周家光, 等(Yan Haixue, et al). 无机材料学报(Journal of Inorganic Materials), 2000, 15(2): 209-220. [6] Dorrian J F, Newnham R E, Smith D K. Ferroelectrics, 1971, 3: 17-21. [7] Cummins S E, Cross L E. J. Appl. Phys., 1968, 39: 2268-2274. [8] Villegas M, Caballero A C, Moure C, et al. J. Am. Ceram. Soc., 1999, 82: 2411-2416. [9] Shulman H S, Testorf M, Damjanovic D, et al. J. Am. Ceram. Soc., 1996, 79: 3124-3128 [10] Villegas M, Caballero A C, Moure C, et al. J. Eur. Ceram. Soc., 1999, 19: 1183-1186. [11] W. D. 金格瑞等 著, 清华大学无机非金属材料教研组 译. 陶瓷导论, 第一版. 北京: 中国建筑工业出版社, 1982. 455-464. [12] Bouzid A, Gabbay M, Fantozzi G. Mater. Sci. Eng., 2004, A 370: 123-126. [13] Kim S K, Miyayama M, Yanagida H. Mater. Res. Bull., 1996, 31: 121-131. [14] Wu Y, Forbess M J, Seraji S, et al. J. Appl. Phys., 2001, 89: 5647-5652. [15] Ehara S, Muramatsu K, Shimazu M, et al. Jpn. J. Appl. Phys., 1981, 20: 877-881. [16] Chan N H, Sharma R K, Smyth D M. J. Am. Ceram. Soc., 1982, 65: 167-170. [17] Wang Z Y, Chen T G. Phys. Stat. Sol. A, 1998, 167: R3-R4. [18] Bao Z H, Yao Y Y, Zhu J S, et al. Mater. Lett., 2002, 56: 861-866. [19] Forbess M J, Seraji S, Wu Y, et al. Appl. Phys. Lett., 2000, 76: 2934-2936. [20] Noguchi Y, Miyayama M. Appl. Phys. Lett., 2001, 78: 1903-1905. [21] Friessnegg T, Aggarwal S, Ramesh R, et al. Appl. Phys. Lett., 2000, 77: 127-129. [22] Buessem W R, Cross L E, Goswami A K. J. Am. Ceram. SoC., 1966, 49: 33-36. [23] 钟维烈. 铁电体物理学, 第一版. 北京：科学出版社, 1996. 304-305. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%