Magnetoelectric composites combining ferromagnetic cobalt ferrite (CFO) and ferroelectric barium titanate (BT) are prepared using conventional solid-state reaction. Dielectric measurements reveal that CFO and CFO-BT composites exhibit Maxwell–Wagner polarization and temperature-dependent relaxation originating due to the presence of ions/defects vacancies. Prominently, CFO-30%BT composite showed an unexpected low dielectric loss ≈ 0.5 above 1 kHz and has potential for device application. Impedance spectroscopy confirms the thermally activated relaxation mechanism and high impedance behavior in the samples. Modulus analysis affirms the statistically distributed non-Debye-type behavior existing in CFO-BT composites. The electric conductivity takes place via correlated barrier hopping in CFO and CFO-10BT composite and overlapping large polaron tunneling in CFO-30BT composite. The addition of BT in CFO initiates the structural modification and results in conductivity cross-over with improved conductivity. These results are useful for exploring devices based on CFO-BT composites.

中文翻译：

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CoFe 2 O 4 -BaTiO 3复合材料的阻抗谱和导电行为

使用常规的固态反应制备了结合了铁磁钴铁氧体（CFO）和铁电钛酸钡（BT）的磁电复合材料。介电测量表明，由于存在离子/缺陷空位，CFO和CFO-BT复合材料表现出Maxwell-Wagner极化和与温度有关的弛豫。突出的是，CFO-30％BT复合材料在1 kHz以上显示出出乎意料的低介电损耗≈0.5，具有在器件中应用的潜力。阻抗谱证实了样品中的热活化弛豫机理和高阻抗行为。模量分析证​​实了CFO-BT复合材料中存在统计上分布的非德拜型行为。电导率通过CFO和CFO-10BT复合材料中的相关势垒跳跃以及CFO-30BT复合材料中的重叠大极化子隧穿来发生。在CFO中添加BT会引发结构修饰，并导致电导率交叉，并改善电导率。这些结果对于探索基于CFO-BT复合材料的设备很有用。