Phase-Equilibrium-Dominated Vapor−Liquid−Solid Growth Mechanism

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• 作者：Chengyu He ; Xizhang Wang ; Qiang Wu ; Zheng Hu ; Yanwen Ma ; Jijiang Fu ; Yi Chen
• 刊名：Journal of the American Chemical Society
• 出版年：2010
• 出版时间：April 7, 2010
• 年：2010
• 卷：132
• 期：13
• 页码：4843-4847
• 全文大小：245K
• 年卷期：v.132,no.13(April 7, 2010)
• ISSN：1520-5126

文摘

The vapor−liquid−solid (VLS) growth model has been widely used to direct the growth of one-dimensional (1D) nanomaterials, but the origin of the proposed process has not been experimentally confirmed. Here we report the experimental evidence of the origin of VLS growth. Al₆₉Ni₃₁ alloyed particles are used as “catalysts” for growing AlN nanowires by nitridation reaction in N₂−NH₃ at different temperatures. The nanowire growth occurs following the emergence of the catalyst droplets as revealed by in situ X-ray diffraction and thermal analysis. The physicochemical process involved has been elucidated by quantitative analysis on the evolution of the lattice parameters and relative contents of the nitridation products. These direct experimental results reveal that VLS growth of AlN nanowires is dominated by the phase equilibrium of the Al−Ni alloy catalyst. The in-depth insight into the VLS mechanism indicates the general validity of this growth model and may facilitate the rational design and controllable growth of 1D nanomaterials according to the corresponding phase diagrams.