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Title: Doped, conductive SiO2 nanoparticles for large microwave absorption

Although many materials have been studied for the purpose of microwave absorption, SiO2has never been reported as a good candidate. In this study, we present for the first time that doped, microwave conductive SiO2nanoparticles can possess an excellent microwave absorbing performance. A large microwave reflection loss (RL) of −55.09 dB can be obtained. The large microwave absorption originates mainly from electrical relaxation rather than the magnetic relaxation of the incoming microwave field. The electrical relaxation is attributed to a large electrical conductivity that is enabled by the incorporation of heterogeneous (N, C and Cl) atoms. The removal of the magnetic susceptibility only results in a negligible influence of the microwave absorption. In contrast, the removal of the heterogeneous atoms leads to a large decrease in the electrical conductivity and microwave absorption performance. Meanwhile, the microwave absorption characteristics can be largely adjusted with a change of the thickness, which provides large flexibility for various microwave absorption applications.

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Publication Date:
Journal Name:
Light: Science & Applications
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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