• • Bi2Se3 nanosheets achieve a broad microwave absorption bandwidth of 2.95 GHz at sub-millimeter thickness, enabling effective EM attenuation in compact form factors.
• • A multilayered design using a single Bi2Se3 absorbent realizes full-band absorption from 2 to 18 GHz, covering radar and communication bands without multiple materials.
• • The Seebeck coefficient of -152 μV/K (measured over 0–110 °C) confirms thermoelectric conversion capability, allowing waste EM energy to be harvested as electricity.
• • Morphology control via polyol reduction allows tuning of nanosheet thickness and size, directly influencing dielectric properties and absorption performance.