Facile synthesis of yolk-shell Ni@void@SnO2（Ni3Sn2） ternary composites via galvanic replacement/Kirkendall effect and their enhanced microwave absorption properties

作     者：Biao Zhao Xiaoqin Guo Wanyu Zhao Jiushuai Deng Bingbing Fan Gang Shao Zhongyi Bai Rui Zhang 

作者机构：Provincial Key Laboratory of Aviation Materials and Application Technology Zhengzhou University of Aeronautics Zhengzhou 450046 China School of Mechatronics Engineering Zhengzhou University of Aeronautics Zhengzhou 450046 China School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2017年第10卷第1期

页      面：331-343页

核心收录：

学科分类：07[理学] 

基　　金：Acknowledgements The authors appreciate the financial support from the National Natural Science Foundation of China (No. 51402264)  and China Postdoctoral Science Foundation (No. 2014M561996) 

主　　题：yolk-shelLNi@void@SnO2(Ni3Sn2) galvanic replacement Kirkendall effect microwave absorption 

摘      要：Yolk-shell ternary composites composed of a Ni sphere core and a SnO2（Ni3Sn2） shell were successfully prepared by a facile two-step method. The size, morphology, microstructure, and phase purity of the resulting composites were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy （TEM）, high-resolution TEM, selected-area electron diffraction, and powder X-ray diffraction. The core sizes, interstitial void volumes, and constituents of the yolk-shell structures varied by varying the reaction time. A mechanism based on the time-dependent experiments was proposed for the formation of the yolk-shell structures. The yolk-shell structures were formed by a synergistic combination of an etching reaction, a galvanic replacement reaction, and the Kirkendall effect. The yolk-shell ternary SnO2 （Ni3Sn2）@Ni composites synthesized at a reaction time of 15 h showed excellent microwave absorption properties. The reflection loss was found to be as low as -43 dB at 6.1 GHz. The enhanced microwave absorption properties may be attributed to the good impedance match, multiple reflections, the scattering owing to the voids between the core and the shell, and the effective complementarities between the dielectric loss and the magnetic loss. Thus, the yolk-shell ternary composites are expected to be promising candidates for microwave absorption applications, lithium ion batteries, and photocatalysis.