Silica-coated iron nanocubes: preparation, characterization and application in microwave absorption.
Novel cubic nanocapsules consisting of metallic iron core and amorphous silica shell were fabricated through a simple chemical reduction route followed by a Stöber process. Thus-prepared Fe@SiO(2) nanocubes were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectrometer (XPS), Fourier transform infrared spectrometer (FTIR), thermogravimetry-differential thermal analysis (TG-DTA), vibrating sample magnetometer (VSM) and scalar network analysis (SNA). Comparing with that of pure iron counterparts, silica-coated iron nanocubes exhibited improved magnetic properties, oxidation resistance and microwave absorption performance. A reflection loss (RL) exceeding -12 dB was obtained in the frequency range of 8-14 GHz for an absorber thickness of 2 mm, with an optimal RL of -18.2 dB at 9 GHz. Mechanism of the improved microwave absorption properties of the Fe@SiO(2) composite was discussed based on their magnetic properties and electromagnetic theory.
Ni
Xiaomin
X
State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China. nxmin@ustc.edu.cn
Zheng
Zhong
Z
Hu
Xiang
X
Xiao
Xiukun
X
D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D008872:Microwaves; D049329:Nanostructures / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
D012822:Silicon Dioxide; D007501:Iron