Interface compatibility engineering of Multi-shell Fe@C@TiO2@MoS2 heterojunction expanded microwave absorption bandwidth

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-02, Vol.429, p.132191, Article 132191
• Main Authors: Huang, Mengqiu, Wang, Lei, Liu, Qi, You, Wenbin, Che, Renchao
• Format: Article
• Language: English
• Subjects: Core-shell; Interface; Microwave absorption; MoS2; Polarization
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2021.132191

Benefitted from enhanced interfacial polarization and synergy magnetic-dielectric loss, multi-shell Fe@C@TiO2@MoS2 microsphere exhibit outstanding microwave absorption. The minimum reflection loss reach to −54.2 dB at 2.5 mm and the efficient absorption bandwidth can cover ∼9.6 GHz only 2.0 mm, which covers the whole X-band and Ku-band. [Display omitted] •Multi-shell Fe@C@TiO2@MoS2 were constructed by an interface compatibility strategy.•The polarization is promoted by compatible interfaces Fe-C, C-TiO2 and TiO2-MoS2.•Hierarchical Fe@C@TiO2@MoS2 displayed remarkable microwave absorption performance. Due to the unique interfacial polarization and the synergy magnetic-dielectric loss, multi-component core–shell microspheres have been attracting extensive attention as Microwave absorption (MA) materials. However, the combination of different dielectric shells to regulate the wider microwave frequency response range still remains a huge challenge, which limits the final practical application. Herein, a hierarchical multi-shell Fe@C@TiO2@MoS2 (FCTM) microsphere is fabricated via an in-situ reduction process. By tuning the types and numbers of dielectric shell surrounding on the magnetic Fe core, the complex permittivity of obtained core–shell MA microspheres could be optimized to extend the absorption bandwidth. In our FCTM microspheres, the hierarchical interfacial polarization can be significantly promoted by forming compatible interfaces involving Fe-C, C-TiO2 and TiO2-MoS2. Dielectric dissipation was much promoted via the designed intermitted carbon layer which contributes remarkable conduction loss, while the magnetic loss capability was boosted by the coupling effects among adjacent microspheres. Consequently, the multi-shell Fe@C@TiO2@MoS2 composites exhibit an excellent MA performance with the minimum reflection loss (RLmin) of −54.2 dB at 2.5 mm. Importantly, the efficient absorption bandwidth (RL