MOF-Guest complex derived Cu/C nanocomposites with multiple heterogeneous interfaces for excellent electromagnetic waves absorption

Electrical conductivity and interfacial polarization are two crucial factors to design high-performance electromagnetic absorption (EMA) materials, but how to synergistically balance these factors still remains to be difficult. In this work, we report the synthesis of Cu/C nanocomposites via the controlled pyrolysis of a MOF-guest complex. The prepared Cu/C nanocomposites are made up of cross-linked carbon network and various irregular particles. The carbon network provides appropriate electrical conductivity to contribute to the conductance loss. Multiple heterogeneous interfaces, such as Mo2C/C, Mo2C/CuO, CuO/C, Mo2C/Cu, and Cu/C interfaces, have been determined in these Cu/C nanocomposites, resulting in obviously improved polarization loss. As a result, the Cu/C nanocomposite exhibits excellent EMA performance, where the efficient absorption bandwidth reaches 6.8 GHz, and the maximal absorption gets to 52 dB. This research provides new idea to design high-performance EMA nanocomposites by tuning the electrical conductivity and interfacial polarization.