Impedance matching optimization of hierarchical carbon fiber@MoS₂@PANI nanocomposite with core‐sheath structure for achieving excellent microwave absorption

Abstract

Carbon fiber (CF) has been extensively used in the research of microwave absorption owning to its excellent performance, but it also faces a series of problems such as impedance mismatch and low absorption intensity. The core‐sheath microstructure with CF as the inner core is constructed to solve the above issues by the introduction of other sheath layers. In this work, the MoS2 sheath and polyaniline (PANI) sheath are successively introduced into the CF matrix to obtain a hierarchical CF@MoS2@PANI nanocomposite with core‐sheath structure through a straightforward hydrothermal method and in‐situ polymerization. The obtained CF@MoS2@PANI nanocomposite exhibit the minimum reflection loss value of −42.23 dB at 10.11 GHz while the thickness is 2.5 mm, much higher than those of pure CF (below −10 dB) and CF@MoS2 nanocomposite (−25.60 dB). Moreover, the distinctive hierarchical core‐sheath structure contributes to providing more active sites, prolonging the transmission path of electromagnetic waves, and forming heterogeneous interfaces. Consequently, the electromagnetic wave attenuation mechanism of CF@MoS2@PANI nanocomposite is attributed to a synergistic effect of conductive loss, multiple reflection/scattering, dipole polarization, and interface polarization. This work offers an effective and promising strategy to design a three‐dimensional hierarchical core‐sheath microstructure for the development of composite absorbers.

MoS2-Based Nanocomposites for Microwave Absorption: A Review

“…If the microstructure of MoS 2 could be modified or constructed in the actual application environment of two-dimensional materials, and the structure–activity relationship of defects or interfaces could be introduced through qualitative characterization and analysis, the dielectric microwave absorption mechanism of MoS 2 could be effectively explored, and the application prospect of low-dimensional transition metal sulfides in the field of microwave absorption could finally be expanded. In addition, the microwave absorption of single MoS 2 is poor, so researchers are devoted to studying composite materials of MoS 2 . − Whether it is composited with dielectric materials or magnetic materials, the microwave absorption performance could be improved. − The schematic illustrations of some representative MoS 2 -based microwave absorption composites are shown in Figures b and c.…”