Core@shell CoNi2S4/Co9S8@SiO2@MoS2 flower-like multicomponent nanocomposites: An effective strategy to aggrandize interfacial polarization for microwave absorption

Abstract

Interfacial polarization had a great impact on the attenuation of electromagnetic wave. To aggrandize interfacial polarization, a strategy of constructing the abundant interfaces was proposed and investigated. Herein, CoNi nanospheres, CoNi@SiO2 nanospheres and core@shell CoNi2S4/Co9S8@SiO2@MoS2 flower-like multicomponent nanocomposites (MCNCs) were elaborately designed and successfully fabricated through a simple continuous hydrothermal process, classical Stöber method and hydrothermal treatment. The obtained results demonstrated that the elaborately constructed abundant interfaces greatly boosted the polarization loss ability, which resulted in the enhanced interfacial polarization. Therefore, the as-prepared CoNi2S4/Co9S8@SiO2@MoS2 flower-like MCNCs presented the superior electromagnetic wave absorption properties (EMWAPs) compared to the CoNi and CoNi@SiO2 precursors. Furthermore, the EMWAPs of CoNi2S4/Co9S8@SiO2@MoS2 flower-like MCNCs could also be further improved by optimizing the hydrothermal temperature and filler loading. The obtained CoNi2S4/Co9S8@SiO2@MoS2 flower-like MCNCs presented the excellent comprehensive EMWAPs including strong absorption capability, broad absorption bandwidth and thin matching thickness, which could be attributed to the unique structure, excellent interfacial polarization and synergistic effect. Therefore, this finding not only demonstrated that introducing the abundant interfaces was an effective strategy to strengthen interfacial polarization for the promotion of EMWAPs, but also provided an alternative approach to exploit the novel high-efficiency microwave absorbers.