In situ anisotropic NiO nanostructure growth at high temperature and under water vapor
In situ anisotropic NiO nanostructure growth at high temperature and under water vapor
复制标题
高温水蒸气下原位各向异性 NiO 纳米结构生长
DOI：
10.1111/jace.18260
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发表时间：
2021
影响因子：
3.9
通讯作者：
van Benthem, Klaus
中科院分区：
文献类型：
--
作者：
Qu, Boyi;van Benthem, Klaus
在800°C的环境扫描电子显微镜(ESEM)中，在水蒸气气氛下进行了原位加热实验，观察到单个镍纳米颗粒的纳米结构的各向异性生长。纳米结构的形貌呈单向生长，生长速率低于1.8 nm/S。能谱和选区电子衍射证实了生长的纳米结构的NiO化学计量比。氧分压在非原位退火过程中的变化和原位ESEM加热实验表明，在局部表面能量密度相对较高的区域，各向异性NiO的生长是有利的。在干燥的空气和干燥的氮气环境中没有NiO纳米结构的生长，需要水蒸气的存在。这项研究的结果表明，在高温下暴露在水蒸气中之前操纵表面能量可以防止不想要的氧化物纳米结构的生长。
Anisotropic growth of nanostructures from individual nickel nanoparticles was observed during in situ heating experiments in an environmental scanning electron microscope (ESEM) at 800°C under water vapor atmosphere. The morphology of nanostructures exhibited one directional growth with rates ranging below 1.8 nm/s. Energy dispersive X‐ray spectroscopy and selected area electron diffraction confirmed NiO stoichiometry of the growing nanostructures. Variations of the oxygen partial pressure during ex situ annealing and in situ ESEM heating experiments elucidate that anisotropic NiO growth is energetically favored in areas where the local surface energy density is relatively high. Growth of NiO nanostructures was absent in dry air and dry nitrogen environments and required the presence of water vapor. The results of this study suggest that the manipulation of surface energy prior to exposure to water vapor at elevated temperatures can prevent unwanted oxide nanostructure growth.