Controllable synthesis of porous M_xS@C composites (M = fe, Cu, Mn) with highly efficient electromagnetic absorption properties

As the frequency range of electronic devices gradually expands, exploring frequency insensitive electromagnetic wave adsorption (EWA) materials that can achieve effective absorption in all bands has aroused great interest. A series of Fe_1 − xS@C composite materials with three-dimensional conductive networks were successfully prepared in this work. In the preparation process, poly (aryl ether sulfone) with branched carboxylic (PAES-C) was selected as the skeleton and Fe³⁺ ions were introduced via chemical adsorption. The main purpose of this work was to develop array porous composite materials with good EWA property. The work proposed a novel controllable method for preparing metal sulfides to explore the electromagnetic wave absorption. This routine was also developed to prepare other M_xS@C composites (M = Fe, Cu, Mn). Compared to Mn_xS@C and Cu_xS@C composites, the RL_min value of Fe_1 − xS@C-4 was − 40.6 dB at 13.52 GHz, and at a thickness of 1.5 mm the effective bandwidth reached 3.12 GHz. Furthermore, its effective absorption band covered Ku, X, and C radar bands at different thicknesses.