Co/C Composite Derived from a Newly Constructed Metal–Organic Framework for Effective Microwave Absorption

The discovery of efficient electromagnetic wave absorbing materials for solving serious electromagnetic wave pollution is an urgent task. By rational design and assembly, a new three-dimensional metal–organic framework (MOF, CPT-1-Co) with the Co ions was constructed and employed as the precursor for the fabrication of Co/C composites via pyrolysis at high temperatures. The resultant Co/C composite pyrolyzed at 700 °C can absorb more than 90% of an EM wave at 2–18 GHz by the alternation of fabrication thickness. The effective absorption bandwidth can reach as high as 5.4 GHz at a thin thickness of 1.7 mm, which is superior to that of most EM wave absorbers. The bottom-up protocol in this report represents the first attempt to pyrolyze a new MOF for microwave absorber fabrication, which will provide valuable insight for designing more advanced MOFs and their applications in efficient electromagnetic wave absorption.