In this paper, we report about the enhanced optical and dielectric properties of ( Zr, Cu ) dual-doped ceramics prepared by cost-effective sol-gel method. The variation in optical and electrical parameters with increased Zr concentration was studied in detail. The UV–visible spectra showed absorption peaks at 350 nm and 440 nm for all the samples. The optical bandgap energy of the Bi 1-x Zr x Fe 0.98 Cu 0.02 O 3 system was found to decrease from 2.41 to 1.78 eV as a measure of Zr concentration. Reduced bandgaps show the potential of these ferrites in visible light photocatalysis. With increase in frequency, the dielectric constant and dielectric loss were found to decrease without any resonance peak while the electrical conductivity increased. At 1 MHz, the dielectric constant (ε′) value as high as 8702 has been achieved for the doped sample. Impedance spectroscopy confirmed the semiconductor behavior of the ferrites. The Nyquist plots favor the non-Debye relaxation process. A remarkable improvement in the dielectric response of the ( Zr, Cu ) dual-doped BiFeO 3 is observed which favors reduced eddy current loss thereby increasing its application in high-frequency devices.

中文翻译：

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(Zr, Cu) 离子置换对 BiFeO3 的光学、介电和阻抗行为的影响

在本文中，我们报告了通过具有成本效益的溶胶 - 凝胶法制备的（Zr，Cu）双掺杂陶瓷的增强的光学和介电性能。详细研究了随着 Zr 浓度增加的光学和电学参数的变化。紫外-可见光谱显示所有样品在 350 nm 和 440 nm 处有吸收峰。发现作为 Zr 浓度的量度，Bi 1-x Zr x Fe 0.98 Cu 0.02 O 3 系统的光学带隙能量从 2.41 降低到 1.78 eV。减少的带隙显示了这些铁氧体在可见光光催化中的潜力。随着频率的增加，发现介电常数和介电损耗降低而没有任何共振峰，而电导率增加。在 1 MHz 时，掺杂样品的介电常数 (ε') 值高达 8702。阻抗谱证实了铁氧体的半导体行为。奈奎斯特图有利于非德拜松弛过程。观察到 (Zr, Cu) 双掺杂 BiFeO 3 的介电响应显着改善，这有利于降低涡流损耗，从而增加其在高频器件中的应用。