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无机材料学报

无机材料学报 ›› 2010, Vol. 25 ›› Issue (5): 473-479.DOI: 10.3724/SP.J.1077.2010.00473 CSTR: 32189.14.SP.J.1077.2010.00473

• 研究论文 • 上一篇    下一篇

高压下纳米La0.8Sr0.2MnO3块状材料的成型及性能研究

黄 浩1, 邵光杰2, 胡 婕1, 2   

  1. 燕山大学 1. 亚稳材料制备技术与科学国家重点实验室; 2. 环境与化学工程学院, 秦皇岛 066004
  • 收稿日期:2009-10-21 修回日期:2009-12-10 出版日期:2010-05-20 网络出版日期:2010-05-12

Study on Molding and Performance for Nanometer La0.8Sr0.2MnO3 Massive Material under High

HUANG   Hao1, SHAO  Guang-Jie2, HU   Jie1, 2   

  1. 1. State Key Laboratory of Metastable Materials Science & Technology, Yanshan University, Qinhuangdao 066004, China; 2. Department of Environment and Chemistry, Yanshan University, Qinhuangdao 066004, China
  • Received:2009-10-21 Revised:2009-12-10 Published:2010-05-20 Online:2010-05-12

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2087

被引次数

1

摘要：

在高压条件下制备出了晶粒尺寸为30nm左右的La0.8Sr0.2MnO3块状材料. 采用X 射线衍射仪(XRD)和场发射扫描电子显微镜(FESEM)对高压样品的相组成、晶粒尺寸及微观形貌进行了表征; 利用显微拉曼光谱仪测量了不同压力下制备出的块状样品在激光功率为400mW时位于100~3000cm-1之内的拉曼光谱. 结果表明, 高压烧结时样品的晶粒演化受温度和压力的共同影响：300℃以下时, 1~3GPa烧结的样品晶粒生长速度随压力的升高而增大, 4~5GPa烧结的样品其晶粒生长速度随压力的升高而减小; 300℃以上时, 其晶粒生长速度随压力和温度的升高而不断增大. 测量了高压烧结后纳米La0.8Sr0.2MnO3块状材料的各种物理性能, 结果表明, 高压烧结后该材料的显微硬度显著提高; 当烧结温度为300℃时, 不同压力下制得的样品的电阻率随压力的升高呈先减小后增大的趋势; 5GPa, 300℃时制出的样品在室温下呈典型的铁磁性能.

关键词: 高压, La0.8Sr0.2MnO3纳米材料, 性能

Abstract:

The La0.8Sr0.2MnO3 massive samples were prepared with crystal grain size about 30nm under high pressure . The structure, grain size and morphology of the samples were characterized by Xray diffraction (XRD) and field emission scanning electron microscope(FESEM). Raman spectra of the samples was carried out by microRaman spectrometer in the range of 100-3000cm-1 with the laser power of 400mW. The results showed that the grain evolution of La0.8Sr0.2MnO3 was influenced by temperature and pressure. When the agglomeration temperature was below 300℃, the grain growth rate increased with increasing pressure at the sintering pressure of 1-3GPa while it fell down as pressure rised continuously at the sintering pressure of 4-5GPa. The grain growth rate increased with increment of pressure when the agglomeration temperature was over 300℃. Physical properties of agglomeration samples synthesized under high pressure were studied. Experimental results indicated that the microhardness of samples increased obviously after high pressure agglomeration. When sintering temperature was 300℃, the resistivity of samples decreased firstly then increased with increment of pressure. The sample prepared under 5GPa at 300℃ had obviously ferromagnetic character at room temperature.

Key words: high pressure, La0.8Sr0.2MnO3 nano-material, performance

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