Novel ZnFe2O4@MnO2@MXene composites with ultrathin thickness and excellent electromagnetic absorption performance

Abstract

A flower-like ZnFe2O4@MnO2 composite with core-shell structures was prepared by a hydrothermal method. MXene nanosheets were fabricated by etching titanium aluminium carbide (Ti3AlC2) and further ultrasonic exfoliation. A ZnFe2O4@MnO2@MXene composite was synthesized by electrostatic self-assembly with negatively charged MXene nanosheets and positively charged ZnFe2O4@MnO2 composite. MXene nanosheets, having a large specific surface area and high electrical conductivity, can provide more conductive pathways. The incorporation of ZnFe2O4 and MnO2 contributes to enhanced interfacial polarization and impedance matching. The ZnFe2O4@MnO2@MXene composite shows better electromagnetic wave absorption (EMA) performance than ZnFe2O4 and the ZnFe2O4@MnO2 composite. The minimum reflection loss (RLmin) of the ZnFe2O4@MnO2@MXene composite reaches −50.4 dB at a frequency of 15.3 GHz with a thickness of 1.40 mm, while the effective absorption bandwidth (EAB) reaches 4.7 GHz (13.3–18.0 GHz). The EMA mechanism of the composite was revealed. This study can provide a strategy for the structural designation of high-performance EMA materials.