标题：Three-dimensional conductive network constructed by in-situ preparation of sea urchin-like NiFe2O4 in expanded graphite for efficient microwave absorption

入藏号：WOS:001049381200001

中国科学院文献情报中心期刊分区：化学1区TOP（2023）

本校作者：邓双林；姜杰*；吴丹；何秦川；王益群*

来源出版物：JOURNAL OF COLLOID AND INTERFACE SCIENCE  卷: 650  页: 710-718

出版年：2023

第一地址： 成都理工大学

关键词：Sea urchin-like NiFe2O4；Expanded graphite；RCS simulation；Electromagnetic wave absorption

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摘要：Expanded graphite (EG) is a modified  conductive lamellar carbon that has been widely studied in the field ofelectromagnetic wave absorption due to its low density, good electrical conductivity, and unique structure.However, its application is limited because the interlayer gap cannot match microwave wavelength, and itssingle composition has less microwave loss. In this study, sea urchin-like NiFe2O4/EG composites are prepared insitu between expanded graphite layers by microwave treatment. The sea urchin-like NiFe2O4 grows between theexpanded graphite to form a three-dimensional conductive network structure, which enhances conductive loss ofcomposites and further increases the interlayer distance of EG. The extended interlayer distance promotesmultiple reflections and scattering of electromagnetic waves in composites and improves dielectric properties. Inaddition, EG with a large specific surface area provides many active sites, further promoting interface and dipolepolarization. Benefiting from synergistic effect of NiFe2O4 and EG, magnetic loss and dielectric loss of NiFe2O4/EG composites have been improved and impedance matching is further enhanced. The results indicate that theminimal reflection loss of NiFe2O4/EG-4 reaches − 53.47 dB at 2.69 mm, and the effective absorption bandwidthreaches 2.97 GHz. In addition, based on the computer simulation technology results, NiFe2O4/EG can attenuatemicrowave energy under experimental conditions. This work provides a strategy for synthesizing carbon matrixcomposites with adjustable dielectric parameters and electromagnetic wave properties. 

文章链接地址: https://www.sciencedirect.com/science/article/pii/S0021979723012523