Construction of MoS2@activated carbon fiber (ACF) composites with rich heterogeneous core-shell structure for enhanced microwave absorption properties

Coal tar pitch-based activated carbon fiber (ACF) is a carbon-based functional material characterized by a high specific surface area, a rich microporous structure, and excellent electrical conductivity, which demonstrates significant potential for electromagnetic wave absorption. To further improve its wave absorption efficiency, this study successfully developed a series of MoS2‐coated ACF composite wave-absorbing materials (MoS2@ACF), using ACF as the carrier through a facile hydrothermal method. By precisely tuning the hydrothermal temperature, remarkable microwave absorption performance was achieved. At a hydrothermal temperature of 190℃, the MoS2@ACF composite exhibited a minimum reflection loss of -32.27 dB at a thickness of 3.5 mm. And at a thickness of 1.5 mm, it achieved an effective absorption bandwidth (RL < -10 dB) of 4.64 GHz. MoS2 demonstrated uniform coating and moderate growth on the ACF surface, resulting in a dense shell structure with appropriate microcracks. This configuration optimizes the dielectric constant of the material, improves impedance matching, enhances the interface polarization effect, and facilitates the synergistic interaction of multiple loss mechanisms between MoS2 nanosheets and ACF. Furthermore, this work presented a viable strategy for the design and development of novel wave-absorbing materials based on activated carbon fiber.