ZnO/nitrogen-doped carbon nanocomplex with controlled morphology for highly efficient electromagnetic wave absorption

In this work, zeolitic imidazolate framework-8(ZIF-8) with yolk-shell and hollow structures were prepared by a convenient chemical etching method. A subsequent pyrolysis of ZIF-8 enabled one to produce Zn O/nitrogen-doped carbon nanocomplexes with original ZIF-8 morphology, where hollow structure showed superior electromagnetic wave absorption capacity and was responsible for matching the impedance of free space. The minimum reflection coefficients of hollow Zn O/nitrogen-doped carbon nanocomplexes were -51.2 d B(700 ℃) and-52.4 d B(800 ℃), respectively, whereas the effective absorption band width was as large as 4 GHz and the content of pyrolyzed hollow ZIF-8 was 15 wt%, which was inferior to the level among similar electromagnetic wave(EMW) absorption materials. The convenient and facile strategy paves the way toward designing hierarchical structures for highly efficient and light-weight electromagnetic wave absorbers.