Investigation of Dielectric Anisotropy and Electrical Modulus-Impedance Properties of PCBM/E7 Composite for Organic Electronic Devices Applications

Abstract

This study investigates the dielectric anisotropy and electrical modulus-impedance properties of a PCBM/E7 composite material for organic electronic devices applications. The research examines a specially fabricated cell combining nematic liquid crystal E7 with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) semiconductor. Through a comprehensive analysis of dielectric anisotropy, AC conductivity, electrical modulus, and impedance characteristics under varying frequencies and applied voltages (-6.0V to +6.0V), the study reveals distinct behavioral regions and multiple relaxation processes. Key findings include frequency-dependent dielectric anisotropy transitions, enhanced AC conductivity at higher frequencies and voltages, and voltage-modulated impedance characteristics. The observed dual-peak phase angle response suggests multiple relaxation mechanisms, indicating the composite's potential for voltage-tunable electrical properties in advanced optoelectronic applications.

Keywords

• AC conductivity
• dielectric anisotropy
• electrical modulus
• impedance spectroscopy
• liquid crystal
• E7-PCBM composite

References

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