Czekaj Dionizy, Lisińska-Czekaj Agata
Faculty of Mechanical Engineering and Ship Technology, Gdańsk University of Technology, 11/12, Narutowicza St., 80-233 Gdańsk, Poland.
Materials (Basel). 2024 May 22;17(11):2491. doi: 10.3390/ma17112491.
In the present paper, composite thin films of barium strontium titanate (BaSrTiO) with an acceptor modifier (magnesium oxide-MgO) were deposited on metal substrates (stainless steel type) using the sol-gel method. The composite thin films feature BaSrTiO ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment at 650 °C, the films were analyzed for their impedance response. Experimental impedance spectra were modeled using the Kohlrausch-Williams-Watts function, revealing stretching parameters (β) in the range of approximately 0.78 to 0.89 and 0.56 to 0.90 for impedance and electric modulus formalisms, respectively. Notably, films modified with 3 mol% MgO exhibited the least stretched relaxation function. Employing the electric equivalent circuit method for data analysis, the "circle fit" analysis demonstrated an increase in capacitance from 2.97 × 10 F to 5.78 × 10 F with the incorporation of 3 mol% MgO into BST-based thin films. Further analysis based on Voigt, Maxwell, and ladder circuits revealed trends in resistance and capacitance components with varying MgO contents, suggesting non-Debye-type relaxation phenomena across all tested samples.
在本论文中，采用溶胶-凝胶法在金属基底（不锈钢类型）上沉积了具有受主改性剂（氧化镁-MgO）的钛酸钡锶（BaSrTiO）复合薄膜。该复合薄膜以BaSrTiO铁电固溶体为基体，MgO线性电介质为增强体，MgO浓度范围为1至5摩尔%。在650℃进行热处理后，对薄膜的阻抗响应进行了分析。使用科尔劳施-威廉姆斯-瓦特函数对实验阻抗谱进行建模，结果表明，对于阻抗和电模量形式，拉伸参数（β）分别在约0.78至0.89和0.56至0.90范围内。值得注意的是，用3摩尔%MgO改性的薄膜表现出最小的拉伸弛豫函数。采用等效电路法进行数据分析，“圆拟合”分析表明，在基于BST的薄膜中加入3摩尔%MgO后，电容从2.97×10 F增加到5.78×10 F。基于沃伊特、麦克斯韦和梯形电路的进一步分析揭示了不同MgO含量下电阻和电容分量的趋势，表明所有测试样品均存在非德拜型弛豫现象。
