Specific-band electromagnetic absorbers derived from metal-organic frameworks

Highly performant electromagnetic absorption (EMA) materials in specific working bands are imperative to mitigate the increasingly severe electromagnetic wave (EMW) pollution caused by advanced electronic equipment. Metal-organic framework (MOF) derivatives and their composites are considered as ideal candidates for regulating the EMA bands due to their unique structural tunability, dimensional diversity, as well as synthetic controllability. Although still in the exploration stage for MOF-based EMA materials and in the trial-and-error period for improving the corresponding properties, the inherent advantages of MOFs make them possess high application prospects in EMA field. Herein, we review the relevant theories and evaluation methods of EMA performance, classify the research reports of MOF-based materials in the field of EMW absorption at S, C, X and Ku bands according to EM parameters, and further summarize the internal relationship among matching frequency (fm), matching thickness (dm), dielectric real part (ε′) and dielectric virtual part (ε″) and proposed a general principle for specific frequency bands. This review would provide theoretical guidance for designing and preparing MOF-based high-efficiency EMA materials from the perspective of specific wavebands, and give full play to the application values of MOF-based materials in the field of EMW absorption.