PANI/Zn‐Cu ferrite polymer composites as free‐standing high dielectric materials

Abstract In a wide range of applications, from consumer electronics to cutting‐edge industrial and scientific equipment, high dielectric permittivity ( ε ′) polymers are crucial for maximizing the performance and efficiency of electrical and electronic systems. Researchers strive to create and perfect these materials to meet the changing demands of modern technology. It is generally known that freestanding bare polymers cannot achieve high dielectric values; however, the mixing of multiple materials that are distinct is an effective technique for developing high dielectric hybrids. Polymer‐based nanoarchitectures are particularly beneficial for use in the storage of energy due to characteristics such as excellent mechanical strength, noncorrosive nature, lightweight, affordability, versatility, thermal and electrical shielding. The primary aim of this investigation is to prepare copper ferrite, zinc ferrite, and copper 0.5 zinc 0.5 ferrite (CuFe 2 O 4 , ZnFe 2 O 4 , and Cu 0.5 Zn 0.5 Fe 2 O 4 ) nanoparticle (NP) via combustion technique using egg albumen as a fuel and these NPs were separately dispersed in polyaniline (PANI) matrix by the method of ex situ polymerization of aniline with an objective to enhance the electrical properties for energy storage and electromagnetic wave applications. Flexible freestanding films were casted via solution casting technique. X‐ray diffractogram of 5 wt.% NP dispersed PANI films confirmed the presence of NPs in the PANI matrix. Scanning electron micrograph images show the homogeneous dispersion of NPs into PANI matrix. Rather than the pure ferrite NPs, mixed ferrite highly enhance the permittivity of PANI films without much increasing its loss factor, the obtained values of ε ′ of all the three ferrite added films are higher than polyvinylidene fluoride (PVDF)/(Mn 0.2 Zr 0.2 Cu 0.2 Ca 0.2 Ni 0.2 )Fe 2 O 4 nanofiller. In this work notably for 5 wt.% Cu 0.5 Zn 0.5 Fe 2 O 4 dispersed film shows the highest value of ε ′ (7291) for 100 Hz at 150°C with ultralow loss factor (0.08) which is the key characteristic of an energy storage material. Thus, this present study leads the formation of a cost effective, flexible, high dielectric material, which can be a potential alternate to replace PVDF/(Mn 0.2 Zr 0.2 Cu 0.2 Ca 0.2 Ni 0.2 )Fe 2 O 4 and polyvinyl alcohol/Ni 0.65 Cu 0.35 Fe 2 O 4 polymer blends for energy storage applications.