Fe Doped Zif-67 Dodecahedrons Anchored on the Enteromorpha Prolifera Derived Biochar with Excellent Microwave Absorption Properties

Abstract

Although the rapid advances of wireless technologies and electronic devices largely improve the quality of life, the omnipresent electromagnetic (EM) pollution increases the risk of exposure to EM radiation. Developing high-efficiency absorbers with rational structure and wideband characteristic is of great significance to eliminate radiation pollution in military or civil fields. Herein, Enteromorpha prolifera derived biochar (EPB) with undulant structure activated by potassium carbonate has been prepared as the supporter to anchor the Fe doped ZIF-67 dodecahedrons. In addition, the EPB with abundant functional groups would provide proper surface and multiple polarization induced by the active sites and thereby contribute to target optimized impedance matching degree and strong energy dissipation. As a result, the as-prepared composite absorbers achieve remarkable EM absorption properties with the minimum reflection loss of -53.9 dB and qualified bandwidth of 4.8 GHz at 2.0 mm attributed to the synergistic magnetic-dielectric dual-loss. Elaborate compositional and structural characterizations indicate the as-prepared composite absorbers have large specific area, and numerous polarization centers, such as Fe heteroatoms, which would make full use of waste biomass as lightweight and broadband high-performance EM absorbing materials.

Keywords: Enteromorpha prolifera derived biochar, Fe doped ZIF-67, Multiple polarization, Microwave absorption properties