Microwave absorption performance of ZnAl2O4

Abstract

The morphological modification has demonstrated that can pave the way of the microwave absorbing materials. The ZnAl2O4 nanoparticles with diverse morphology have been tailored using modified sol-gel and solvothermal methods. 2D structures and hollow blueberry like morphologies of the ZnAl2O4 nanostructures were architected by the sucrose and carbon microspheres as novel templates. X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM) analyses were applied to characterize fabricated nanostructures denoting pure ZnAl2O4 nanostructures have been synthesized having novel morphologies. Noticeably, the surface characteristics of the architected nanoparticles were studied by N2 adsorption-desorption isotherms. Moreover, optical performance of the nanoparticles were evaluated by diffuse reflection spectroscopy (DRS) analysis exhibiting the morphology of the nanoparticles has a considerable influence on the light absorption and energy bad gap. Eventually, a vector network analyzer (VNA) revealed microwave absorbing characteristics of the morphology-modified nanoparticles. It is well known that the interfacial interactions at grain boundaries have salient effect in microwave absorption, dissected in this research using polystyrene (PS) and polyvinylidene fluoride (PVDF) media. The blue berry like nanostructure (BH) demonstrated eye-catching microwave absorbing features. BH/PVDF nanocomposite depicted remarkable reflection loss (RL) (−95.63 dB) at 9.63 GHz with 3.00 mm in thickness meanwhile it displayed an efficient bandwidth as wide as 2.80 GHz (RL < −20 dB) with a thickness of 2.50 mm. Interestingly, BH/PS nanocomposite exhibited a broad efficient bandwidth of 9.14 GHz (RL < −10 dB).