Constructing Multiphase‐Induced Interfacial Polarization to Surpass Defect‐Induced Polarization in Multielement Sulfide Absorbers

Abstract

The extremely weak heterointerface construction of high‐entropy materials (HEM) hinders them being the electromagnetic wave (EMW) absorbers with ideal properties. To address this issue, this study proposes multiphase interfacial engineering and results in a multiphase‐induced interfacial polarization loss in multielement sulfides. Through the selection of atoms with diverse reaction activities, the multiphase interfacial components of CuS (1 0 5), Fe0.5Ni0.5S2 (2 1 0), and CuFe2S3 (2 0 0) are constructed to enhance the interfacial polarization loss in multielement Cu‐based sulfides. Compared with single‐phase high‐entropy Zn‐based sulfides (ZnFeCoNiCr‐S), the multiphase Cu‐based sulfides (CuFeCoNiCr‐S) possess optimized EMW absorption properties (effective absorption bandwidth (EAB) of 6.70 GHz at 2.00 mm) due to the existence of specific interface of CuS (1 0 5)/CuFe2S3 (2 0 0) with proper EM parameters. Furthermore, single‐phase ZnFeCoNiCr‐S into FeNi2S4 (3 1 1)/(Zn, Fe)S (1 1 1) heterointerface through 400 °C heat‐treated is decomposed. The EMW absorption properties are enhanced by strong interfacial polarization (EAB of 4.83 GHz at 1.45 mm). This work reveals the reasons for the limited EMW absorption properties of high‐entropy sulfides and proposes multiphase interface engineering to improve charge accumulation and polarization between specific interfaces, leading to the enhanced EMW absorption properties.

Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo–MXene/Mo–Metal Sulfides for Electromagnetic Response

“…Consequently, through the construction of semiconductor junctions and Mott–Schottky junctions between Mo–MXene, MoS 2 , and metal sulfides, the dielectric loss capability of Mo–MXene/Mo–metal sulfides has been significantly improved, which enhances the EMW absorption performance. The loss mechanisms that have the greatest impact on EMW attenuation is mainly the related polarization loss induced by BIEF [ 67 ]. Our findings emphasize that utilizing solely semiconductor–metal mixed phase or single phase materials results in poor EMW absorption performance.…”

In situ fabrication of Fe3C nanoparticles and porous-carbon composites as high-performance electromagnetic wave absorber

“…In a general context, outstanding EMW absorption materials exhibit robust EMW attenuation capabilities, a broad effective absorption frequency bandwidth, lightweight structures, and thin thicknesses, with these characteristics varying based on distinct application conditions. [7][8][9] Numerous compounds can function as ideal EMW-absorbing material. Traditional EMWabsorbing materials included magnetic metal (Fe, Co, Ni), [10][11][12] their oxide (e.g.…”