Improved Performance of an Electronic Waste Based Cost-Effective Microwave Absorber Using Cavitation

The requisition of cost-effective practical microwave absorbing material (MAM) to deplete electromagnetic (EM) waves has garnered much interest in current times. Aimed at reinforcing the electronic waste (e-waste) management and in the exploration of broadband absorber structure, a compositional variation of the hazardous printed circuit board and zinc-carbon battery cell (Zn-C) is investigated using a facile top-down fabrication technique. The dielectric analysis of samples is carried out in the range of 8.2–12.4 GHz (i.e., X-band) using a waveguide-based microwave measurement technique. A 1.7-mm-thick single-layer absorber achieves a minimum reflection coefficient (RC) of − 24.9 dB at 10.8 GHz with a 2.7 GHz bandwidth (BW) below − 10 dB threshold. Furthermore, the enhancement in absorption BW is accomplished by adding an array of periodic air cavities (grid-type structure) which results in an increase of BW below − 10 dB threshold. Moreover, the integration of planar structure with a grid-type structure imparts more prominent results and acquires 4.0 GHz BW below − 10 dB threshold with 1.7-mm coating thickness. In addition, the influence of the oblique angle of incidence is also investigated for optimized structures. The reliability of the obtained results has been verified by the finite-integration technique via the 3D modeling and EM analysis in computer simulation technology. The inclusion of air gap in the absorbers standardize the EM properties of the composite and result in impedance matching at a higher frequency. The results obtained demonstrate the practicability of the suggested structure and proved to be cutting-edge technology for researchers. It reveals that the e-waste composites have enormous potential in the development of lightweight, broadband, and cost-effective MAM for stealth applications.