Microwave absorption efficiency of double-layer corn husk-based microwave absorber

The present study reports a double-layer microwave absorber using corn husk in the frequency range of 1–20 GHz. By altering the thickness of the first layer and the amount of charcoal in the second layer, absorption properties of two double-layer configurations are investigated. The open-ended coaxial probe method is used to determine the dielectric characteristics and reflection coefficient of each layer in both the single-layer and double-layer configurations. The proposed double-layer configuration is designed in CST Microwave Studio (CST MWS), and the outcome demonstrates the effective absorption performance. Corn husk-based MA is biodegradable, eco-friendly, and non-toxic, making it a viable alternative microwave absorber (MA). Further, easy fabrication method, light weight, and thinnest double-layer configuration provide better absorption performance. The experimentally obtained result shows the utmost absorption performance of − 49.04 dB at 18.271 GHz frequency.