摘要
The well-designed composite with satisfactory electromagnetic microwave absorption at high temperatures remains a serious challenge.Herein,we fabricated a resorcinol-formaldehyde/silica dioxide composite aerogel(RF/SiO_(2))with a three-dimensional network structure using sol-gel,atmospheric pressure drying technique as well as heat-treated processes to achieve enhanced microwave absorption capabilities in the low frequency range.The pristine RF/SiO_(2)aerogel presented a typical micropores structure with a surface area,porous volume,and density of 146.82 m^(2)/g,62.40%,and 0.28 cm^(3)/g,respectively.Remarkably,the RF/SiO_(2)aerogel showed an effective absorption bandwidth of 3.56 GHz and a minimum reflection loss value of-46.10 d B at 2.25 mm after being heat-treated at 1500°C,while the maximum effective absorption bandwidth was 3.60 GHz at 2.30 mm.The intricate three-dimensional networks possessed remarkable impedance matching,multiple attenuation mechanisms,interfacial polarization,and dielectric loss,which were attributed to the exceptional ability to absorb electromagnetic microwaves.It offered a fresh approach to creating adaptable and effective microwave absorption materials in military defense.
基金
supported by the Fundamental Research Funds for the Central Universities(Grant Nos.D5000210522 and D5000210517)
China Postdoctoral Science Foundation(Grant No.2021M702665)
Natural Science Foundation of Shaanxi Province(Grant Nos.2022JQ-482 and 2023-JC-QN-0380)
Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2021A1515111155,2022A1515111200 and 2022A1515011191)
Basic Research Programs of Taicang(Grant Nos.TC2021JC01,TC2021JC21,and TC2022JC08)。