Facile preparation of CoS₂ nanoparticles embedded into polyaniline with tunable electromagnetic wave absorption performance

Electromagnetic wave absorption has attracted wide attention due to electromagnetic wave pollution and radiation. The dielectric loss coating magnetic nanoparticles structure has a significant influence on electromagnetic wave absorption properties. In this manuscript, magnetic nanoparticles (CoS2) coated polyaniline (PANI) are synthesized via a facile and simple two-step strategy (a microwave assisted hydrothermal reaction followed an in-situ free radical chemical oxidative polymerization). The CoS2 nanoparticles are coated by PANI which is used as the matrix of electron conduction during converting electromagnetic energy into thermal energy. The electromagnetic wave absorption properties of PANI@CoS2 nanocomposites can be adjusted by changing the mass ratios of CoS2 and PANI. Compared with that of CoS2 nanoparticles or PANI, the electromagnetic wave absorption properties of PANI@CoS2 nanocomposites were significantly enhanced due to impedance matching and dielectric loss. When the mass ratio of PANI and CoS2 is 1:3, this nanocomposite exhibits excellent electromagnetic wave absorption. The maximum reflection loss can reach to -54.6 dB at electromagnetic wave frequency of 12.1 GHz and effective absorbing bandwidth is 4.76 GHz ranging from 9.63 to 14.39 GHz under corresponding nanocomposites thickness of 2.1 mm. Hence, PANI@CoS2 nanocomposites have potential application in electromagnetic wave absorption.