纳米ZnO作为一种新型吸波材料受到广泛关注,但对非c轴生长的ZnO纳米结构材料的吸波性能还缺乏系统研究.为了探讨ZnO纳米晶体的形貌对其吸波性能的影响,在熔盐、类离子液体等强极性介质中,合成了枝晶状、片状、锥状等非c轴生长的ZnO纳米结构材料,用XRD、SEM、TEM等对其物相、形貌进行了表征,对不同形貌的ZnO纳米结构材料的电磁性能与吸波性能进行了系统的分析,并与商品ZnO微粉的吸波性能进行了比较.结果表明,ZnO纳米片的吸波效果较好.复合了磁性材料后,ZnO的吸波性能有明显提高.
ZnO nanostructures have attracted great interest as promising microwave absorbing materials due to the unique chemical and physical properties. However,ZnO is probably the richest family of nanostructures among all materials, both in structures and in properties. The influence of the morphology of ZnO nanostructures on absorption remains substantially deficient. In this paper, ZnO nano-structures with different morphologies (dendritric, flake,and pyramid) have been synthesized in strongly polar conditions such as molten salt and ionic liquids. X-ray diffraction (XRD) analyses indicated that as-prepared products were pure ZnO with wurtzite structure. The morphologies were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The electromagnetic parameters and microwave absorption properties of the products with different morphologies have been investigated in detail. The results indicated that ZnO flakes bad better microwave absorption performances than the other samples. After combining magnetic materials, such as Fe3O4, the microwave absorption performances of ZnO increase remarkably.