Lightweight and Thin with High-Frequency Performance Microwave Absorbing Heterostructure Carbon Derived from Ashoka-leafs Ash

Abstract

In today's world, there is a significant focus on addressing acute electromagnetic pollution and developing efficient stealth materials. This involves extensive efforts to create high-performance microwave absorption materials (MAMs), with a strong emphasis on sustainability and eco-friendliness. To contribute to proper waste and agriculture waste management which synthesis by carbonization and hydrothermal route, a recent study introduces a novel approach using carbonized leaves as single-layer microwave absorbers made from Ashoka-leafs Ash (AA). These absorbers are extremely slim and lightweight, with a thickness of just 0.5 mm. They have a weight ratio of 1:1 when combined with paraffin wax, and they are engineered to perform efficiently within the high-frequency range of 27–40 GHz (Ka-band). This frequency range is also pertinent to 5G communication technology. The absorbing characteristics of this substance are affected by the greater surface area resulting from the heterostructure. This, in turn, leads to an increase in its capacity for losses, dielectric constant, and conductivity. Consequently, it improves its efficiency in absorbing microwaves. The outcomes reveal that the material attains an impressive reflection loss value of − 45 dB at 34 GHz, with a thickness of 0.5 mm, corresponding to a high attenuation constant and an absorption rate of 99.99%. This exceptional performance suggests that the proposed microwave-absorbing material could be utilized in the development of military, anechoic chambers and low-cost stealth materials. Notably, these results outperform many other carbonaceous materials derived from biomass that have been previously reported. Before conducting the absorption studies, various microstructural characterizations on the material were to better understand its properties and behaviour.