纳米晶钛酸钡的介电性能

采用硬脂酸凝胶法制备了纳米晶BaTiO3,用差热热重分析、红外光谱分析、X射线衍射分析等手段对产物的形成过程、晶型、粒径进行了分析.通过对材料介电性能的研究发现,纳米材料的静态介电常数远大于常规材料的介电常数,随着粒径的减小,纳米材料的介电常数先增大而后有所降低.随着环境湿度的升高,纳米晶材料的介电常数逐渐增大,在高湿度条件下,其介电常数与湿度成线性关系.

Dielectric Properties of Nanocrystalline BaTiO3

Nanocrystalline BaTiO3 is prepared using a stearic acid gel method. The synthesis process, crystalline structure and grain sizes of nanocrystal are investigated by differential thermal analysis, thermogravimetric analysis, infrared spectra and X-ray powder diffraction. The experimental results of dielectric properties of nanocrystal indicate that the dielectric constant ε of nanocrystal is much larger than that of bulk materials. With reducing of grain size, the ε of nanocrystalline material increases first, then it falls to smaller value. With the increment of relative humidity, the ε grows up. The relationship between ε and humidity becomes linear with high enough humidity.