Exploring the synergistic role of graphite and binary metal sulfides in achieving superior electromagnetic wave absorption

Abstract

The escalating issue of electromagnetic microwave pollution necessitates the development of high-efficiency absorbing materials. Composite materials featuring multiple loss mechanisms have emerged as the primary approach for creating effective electromagnetic wave absorbers. Among these, metal sulfides are promising candidates due to their unique properties and controllable microstructures. However, the wave absorption capabilities of single metal sulfides are inherently limited. To enhance their electromagnetic absorption properties, strategies such as morphological regulation and the doping of foreign materials have proven effective. In this study, we reacted nickel powder and iron powder with tin disulfide to synthesize binary metal sulfides. These sulfides were subsequently combined with graphite through ball milling to create a wave-absorbing material characterized by both dielectric and magnetic losses. The formation of suitable heterogeneous interfaces, diverse compositions, and abundant defects enables effective impedance matching and promotes multiple dielectric polarization, thereby synergistically enhancing electromagnetic wave (EMW) absorption capacity. Leveraging these advantages, the Fe-Sn-S binary metal sulfide demonstrates an effective absorption band at 4.46 GHz, achieving a minimum reflection loss (RL_min) of −64.48 dB. This research paves the way for new composite materials designed for improved sulfide-based electromagnetic wave absorption.