Nanoflower ZnO @ NiCo /C@Polypyrrole Nanocomposites for Broadband Electromagnetic Wave Absorption

Abstract

ABSTRACT In recent years, electromagnetic radiation poses a significant risk to the precision of equipment and human health. The fabrication of wave‐absorbing composites with good morphology design by combining with different materials is expected to solve this problem. In here, ZnO@NiCo/C@PPy (ZNCP) nanocomposites with flower‐like structure were synthesized through a combination of chemical, solvothermal, and in situ polymerization techniques. The outer layer of flower‐like ZnO was successfully wrapped with NiCo alloy, and both Ni and Co are magnetic lossy materials. This not only curtails the occurrence of agglomeration phenomenon and facilitates the resonance loss, but also maintains the original flower‐like structure of the material, and the conductive network skeleton of carbon obtained from high‐temperature pyrolysis can multi‐scatter the electromagnetic wave (EMW), which can further effectively deplete the EMW. As expected, the ZNCP nanocomposites exhibit optimal performance, at the frequency of 5.8 GHz reflection loss (RL min ) reaches −81.64 dB with a matching thickness of 5.5 mm, and at 10.64 GHz effective absorption bandwidth (EAB) reaches 4.5 GHz with a matching thickness of 3.13 mm. The findings show that the ZnO@NiCo/C@PPy nanocomposites have excellent EMW absorption performance, which can serve as a reference for designing wave‐absorbing materials with superior structure and performance.