Multi-interface spatial star-like MoC/Co/C composites toward enhanced electromagnetic wave absorption properties

Interfacial engineering and morphology design are two popular strategies to strengthen the performance of carbon-based composites as electromagnetic wave absorbing materials (EWAMs). Herein, we integrate their advantages simultaneously in ternary MoC/Co/C composites (SMCCs). On one hand, highly dispersed MoC and Co nanoparticles create abundant heterogeneous interfaces, and on the other hand, the spatial star-like carbon skeletons derived from ZnCo-MOF also bring significant structure contribution to EM energy consumption. EM measurement reveals that the pyrolysis temperature greatly impacts EM properties of SMCCs. After blending with paraffin (organic binder), the mixture that involves SMCC-800 (pyrolyzed at 800 °C) may have both good impedance matching degree and powerful EM attenuation ability. As a result, SMCC-800/paraffin displays excellent EM absorption performance, including strong reflection loss intensity down to −67.3 dB at 16.2 GHz (thickness: 1.8 mm) and broad response bandwidth of 6.0 GHz (12.0–18.0 GHz, thickness: 2.0 mm) less than −10.0 dB, which outdo the performance of many composites with similar chemical composition ever reported. The EM absorption mechanism of SMCC-800/paraffin is comprehensively illustrated through the investigation on EM properties of the mixtures with various control samples.