Assembling 3D flower-like Co₃O₄-MWCNT architecture for optimizing low-frequency microwave absorption

Effectively absorbing and converting electromagnetic (EM) energy for reutilization has an important implication in the fields of energy and environment. Herein, multi-walled carbon nanotubes (MWCNTs) are confinedly implanted into flower-like cobaltosic oxide (Co₃O₄) to tailor the conductive network and polarization genes. It controllably tunes the EM property and optimizes the low-frequency microwave absorption. The minimum reflection loss reaches −61.4 dB at 3.44 GHz. A novel self-powered device is constructed to achieve the effective conversion from waste EM energy to useful electric energy. Energy conversion process inside flower-like Co₃O₄-MWCNT architecture is investigated, and the contribution of dielectric loss and magnetic loss to energy conversion is exhibited. This work provides a promising approach in combating EM pollution and alleviating energy problem.