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In this article, a comparison of EMI shielding performance of rigid and flexible composites of cobalt nickel ferrite is done. Firstly, the rigid composites are synthesized using a regular ceramic route having three different multiwalled carbon nanotube (MWCNT) concentrations, which are denoted 3MWCNT/CNF, 6MWCNT/CNT, and 9MWCNT/CNF. In order to support their potential use as microwave absorbers in the microwave frequency range, the synthesized rigid composites are examined for their structural, morphological, electromagnetic, and microwave properties using X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), vibrating sample magnetometer (VSM), and vector network analysis (VNA). The 9MWCNT/CNF composite exhibited the best shielding performance of 55.96 dB. Then, the prepared rigid composites were made into highly flexible films of varying thickness. The prepared flexible composites, and their essential EMI shielding parameters are simulated using CST Studio Suite Software, as well as measured experimentally. The agreement between simulated and measured values is exceptionally high. Furthermore, in comparison to traditional rigid composites, the fabricated flexible composites have superior shielding capabilities and operate in the X-band frequency range making them suitable for microwave and flexible technologies. [ABSTRACT FROM AUTHOR]

The flourishing electronic industries and advanced technologies have created an emerging issue by escalating the level of electromagnetic radiation in the environment. In the current investigation, a sophisticated, cutting-edge magnetoelectric composite material is designed and developed in contrast to its counterparts, and exhibits excellent electromagnetic interference shielding performance. A novel multiferroic material composed of ferroelectric BaZr0.2Ti0.8O3 (BZT) and ferromagnetic Co0.75Ni0.25Fe2O4 (CNF) with graphene oxide decoration is developed through a novel microwave sintering technique. The relative permittivity, AC conductivity, magnetic coercivity, and polarization of the composites are all found to be enhanced by the incorporation of graphene oxide into the composite. A high relative permittivity of more than 50k at 10 kHz is observed in the magnetoelectric composite along with relaxor behaviour at 1.5 wt% graphene oxide reinforcement. The magnetoelectric composite's energy storage capacity has been found to be improved by the addition of GO reinforcement. Impedance studies revealed the Debye relaxation behavior for the BZT–CNF composite and composite with 0.5 wt% GO. The performance of the shielding against electromagnetic interference is evaluated in the X-band frequency range. Furthermore, the BZT–CNF composite has the lowest reflection loss (RL) of −54.9 dB with a maximum total shielding efficiency of 66.8 dB, whereas the magnetoelectric composite with 1.5 wt% GO exhibits improved microwave attenuation with the highest specific shielding efficiency of 75.03 dB cm2 g−1 and the maximum total shielding efficiency of 95.44 dB. The discovered material has excellent microwave absorption and shielding properties, making it very useful for radar and stealth technologies in the military, as well as in the electronics, medical, and electronic industries. [ABSTRACT FROM AUTHOR]

The escalating demand for energy-related devices has prompted an intensive study on materials for energy harvesting and storage. Recently, due to the toxicity of lead-based materials, researchers have drawn their attention to lead-free ferroelectrics. However, it is indisputable that commercially lead zirconium titanate (PZT) has gained an irreplaceable position as an actuator. In the present work, we specifically compare microwave-sintered PbZr 0.52 Ti 0.48 O 3 and BaZr 0.20 Ti 0.80 O 3 ceramics based on their energy-storage capacity. The structural, optical, electrical, ferroelectric, and energy storage properties of microwave-sintered Zr-modified lead titanate (PbZr 0.52 Ti 0.48 O 3 , PZT) and Zr-modified barium titanate (BaZr 0.20 Ti 0.80 O 3 , BZT) ceramics are investigated and addressed. The temperature-dependent dielectric property analysis suggests high transition temperature and dielectric properties for PZT ceramic, whereas the near-room temperature transition is observed in the case of BZT. Furthermore, the band-gap energy value of BZT and PZT from UV-vis spectroscopy indicates the possible use of these ceramics in optoelectronic devices. The ferroelectric properties of PZT and BZT are discussed, and the maximum energy storage capacities are found to be 30.5 and 21 mJ/cm 3 for PZT and BZT, respectively. It is found that microwave-sintered PZT's characteristics make it an attractive option for use in filters, phase shifters, sensors, actuators, and energy-related devices. On the other hand, BZT finds its suitability in biomedical devices and underwater applications., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)