In situ-derived carbon nanotubes decorated the surface of CoxNiy@C composites from MOFs for efficient electromagnetic wave absorption

The in situ formation of interconnected carbon nanotubes (CNTs) networks on the surfaces of metal-organic framework (MOF) derivatives is an efficient method for rationally constructing heterogeneous interfaces and developing high-performance electromagnetic wave absorption materials. A series of CoxNiy @C composite absorbers with abundant CNTs on their surfaces prepared by pyrolyzing MOF precursors in an Ar atmosphere is reported in this study. The S-3 composite absorber had a distinct structural morphology, and optimal wave absorption performance was obtained when the final pyrolysis temperature was 800 °C. At matched thicknesses of 2.0 mm and 3.5 mm, an effective absorption bandwidth (EAB) of 4.5 GHz and a minimum reflection loss (RLmin) of −43.5 dB were achieved when the absorber filling ratio was 15 wt%. This strategy and the results reported in this study are anticipated to encourage future studies into the controlled growth of metal-catalyzed CNTs and inspire new ideas for designing and preparing enhanced microwave absorber materials at the micro-nano scale.