Enhanced Microwave Absorption of Polyvinylidene Fluoride Nanocomposites with Spherical Spinel Ferrite CoFe ₂ O ₄ and Rod-Shaped Semiconductive ZnO Nanoparticles

High Resolution Image Download MS PowerPoint Slide The rapid development of telecommunication technologies and electronic devices has led to increased electromagnetic pollution. This growing electromagnetic pollution especially in the microwave range disrupts the performance of sensitive electronics and raises concerns about possible effects on human health. Microwave absorbers have become a focus of extensive research to mitigate this pollution. As communication systems typically operate within the microwave region, the need for efficient microwave absorption materials is greater than ever. It is noted that the morphological engineering is critical for improving interfacial polarization, a key determinant in microwave absorption. This investigation examines the microwave absorption characteristics of polyvinylidene fluoride (PVDF) nanocomposites with CoFe 2 O 4 spinel ferrite spherical and zinc oxide (ZnO) rod-shaped nanoparticles. Spherical CoFe 2 O 4 (cobalt ferrite (CF)) spinel ferrite and ZnO rod-shaped nanoparticles were synthesized using the sonochemical method. The polymer nanocomposites (PVDF/CF/ZnO-1 and PVDF/CF/ZnO-2 with 30 and 40 wt % filler loadings, respectively) were prepared using a simple solution casting procedure. The developed PVDF/CF/ZnO-2 nanocomposite with 3 mm thickness revealed the lowest minimum reflection loss (RL) value of −44.79 dB with an effective absorption bandwidth of 2.46 GHz (below −10 dB of RL). Furthermore, the PVDF/CF/ZnO-2 nanocomposite demonstrates effective solar-to-thermal conversion, achieving a temperature rise to 39 °C under mild 1.5 Sun irradiation and maintaining excellent photothermal stability over multiple on–off cycles. The obtained results indicate that the PVDF/CF/ZnO nanocomposites are promising candidates for application in wearable electronics, aerospace, and military especially in the X-band microwave absorption applications, including radar attenuation layers and microwave absorber components in electronic systems.