Comparative study of microwave absorption in Ni/SiO2 and SiO2/Ni core-shell structures

TL;DR

This study compares microwave absorption in Ni/SiO2 and SiO2/Ni core-shell particles, revealing that electromagnetic properties and impedance matching are key to their absorption performance.

Contribution

It provides a comparative analysis of core-shell structures' electromagnetic properties and their influence on microwave absorption, highlighting the importance of impedance matching.

Findings

Both structures exhibit good microwave absorption.

Effective permittivity and permeability depend on component material properties.

Impedance matching is crucial for optimal absorption.

Abstract

Ni coated SiO2 and SiO2 coated Ni composite particles with core-shell structures were designed, prepared and their microwave absorption properties were characterized. The comparison study of the shell effect on the effective electromagnetic parameters reveals that the effective permittivity/permeability was crucially determined by the percent and the intrinsic electromagnetic parameters of the component materials regardless of various core/shell structures. Both of the composite core-shell structures could have good microwave absorption properties. Investigation of the input impedance indicates that, good microwave absorption performances are a consequence of proper electromagnetic impedance matches when the effective electromagnetic parameters were modulated.