Tea waste biomass-derived microporous carbon for improved microwave absorption

Biomass-derived carbon materials with tailored porosities are attracting significant attention for their promising application in microwave absorption owing to their inherent sustainability and unique structural characteristics. This work investigates the effect of porosity on the microwave adsorption of biomass-derived carbon. Microporous carbon with varying porosities was successfully prepared from green tea waste, and the porous microstructure was systematically modified, with surface areas ranging from ~ 470 to ~ 660 m²g⁻¹, by carbonizing at various temperatures. Porous carbon with optimized porosity exhibits remarkable microwave absorption performance, achieving a minimum reflection loss of − 47.60 dB at a thickness of 2.2 mm and an effective absorption bandwidth (RL < − 10 dB) of 4.88 GHz. The practical viability of the material was further evaluated by computer simulation technology to simulate radar cross-section (RCS) analysis in real-world far-field scenarios. The results demonstrated that the simulated RCS values of optimum porous structure can reach lower than 20 dB, indicating their potential application in reducing the dispersion and reflection of radar waves. Thus, this study determines the potential of utilizing green tea waste for the development of high-performance, sustainable, and economically viable microwave-absorbing materials with exceptional performance.