Submicrometer-sized NiO octahedra: facile one-pot solid synthesis, formation mechanism, and chemical conversion into Ni octahedra with excellent microwave-absorbing properties
Submicrometer-sized NiO octahedra: facile one-pot solid synthesis, formation mechanism, and chemical conversion into Ni octahedra with excellent microwave-absorbing properties
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DOI：
10.1039/c2jm31790g
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发表时间：
2012-08
影响因子：
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通讯作者：
Guoxiu Tong;Guoxiu Tong;Q. Hu;Wen-hua Wu;Wei Li;H. Qian;Yan Liang
中科院分区：
文献类型：
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作者：
Guoxiu Tong;Guoxiu Tong;Q. Hu;Wen-hua Wu;Wei Li;H. Qian;Yan Liang
采用一种简便的无模板一锅热分解法大量制备了亚微米尺寸的NiO八面体。通过在不同温度下对NiO八面体进行H2退火，可以容易地获得具有定制结晶和织构特性的Ni八面体。Ni八面体的良好形貌保持是由于最小表面自由能原理以及与NiO相似的晶体学系统。静态磁性和微波电磁性能的研究揭示了纳米材料的反应性、形状和合成性能之间的关系。由于其高BET比表面积和良好的晶体尺寸，在300 °C下制备的多孔Ni八面体表现出优异的匹配和吸收性能，在12.80 GHz和11.60 GHz带宽下的最小RL值为−37.93 dB（低于−20 dB）。因此，这里描述的Ni八面体被认为具有广泛的应用，包括催化、电磁屏蔽和吸收。
A facile template-free and one-pot thermal decomposition approach was used for the mass preparation of submicrometer-sized NiO octahedra. Ni octahedra with tailored crystallization and texture characteristics are easily achieved through H2-annealing of NiO octahedra at various temperatures. The good morphology retention of Ni octahedra is due to the principle of minimum surface free energy as well as the similar crystallographic system to that of NiO. Studies on static magnetic and microwave electromagnetic properties reveal the relationships among the reactivity, shape, and resultant properties of the nanomaterials. Because of their high BET specific surface area and favorable crystal size, porous Ni octahedra produced at 300 °C exhibit excellent matching and absorbing properties with a minimum RL value of −37.93 dB at 12.80 GHz and 11.60 GHz bandwidth (below −20 dB). Thus the Ni octahedra described here are believed to have a wide range of applications, including catalysis, electromagnetic shielding, and absorption.