The role of surface nonuniformity in controlling the initiation of a galvanic replacement reaction.
The role of surface nonuniformity in controlling the initiation of a galvanic replacement reaction.
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表面不均匀性在控制电取代反应引发中的作用。
DOI：
10.1002/asia.201000944
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Xia,Younan
中科院分区：
文献类型：
--
作者：
Cobley,ClaireM;Zhang,Qiang;Song,Wilbur;Xia,Younan
研究了银纳米晶-不对称截短的八面体和纳米棒-作为原电池置换反应的基底的非均匀表面的用途。由于这些纳米晶体的表面包含具有各种不同面积、形状和原子排列的小平面，因此我们能够检查这些参数在与HAuCl 4的电流置换反应的不同阶段中的作用（例如，点蚀、空洞化、凹坑闭合和孔形成），从而获得比使用银纳米立方体可能的更深的反应机理的理解。我们发现，这些参数中最重要的是原子排列，也就是说，表面是否由{100}或{111}面覆盖，并且面的面积和形状对反应的起始基本上没有影响。有趣的是，通过与不对称截短八面体的反应，我们还能够证明，即使在大面积上发生点蚀，该区域也会在反应的中间阶段通过原子扩散和沉积的组合被密封。因此，即使点蚀发生在大百分比的模板表面上，仍然可以在整个反应过程中保持模板的形态。
The use of silver nanocrystals—asymmetrically truncated octahedrons and nanobars—characterized by a nonuniform surface as substrates for a galvanic replacement reaction was investigated. As the surfaces of these nanocrystals contain facets with a variety of different areas, shapes, and atomic arrangements, we were able to examine the roles of these parameters in different stages of the galvanic replacement reaction with HAuCl4(e.g., pitting, hollowing, pit closing, and pore formation), and thus obtain a deeper understanding of the reaction mechanism than is possible with silver nanocubes. We found that the most important of these parameters was the atomic arrangement, that is, whether the surface was capped by a {100} or {111} facet, and that the area and shape of the facet had essentially no effect on the initiation of the reaction. Interestingly, through the reaction with asymmetrically truncated octahedrons, we were also able to demonstrate that even when pitting occurred over a large area, this region would be sealed through a combination of atomic diffusion and deposition during the intermediate stages of the reaction. Consequently, even if pitting occurred across a large percentage of the nanocrystal surface, it was still possible to maintain the morphology of the template throughout the reaction.
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影响因子：
16.6
作者：
Cobley, Claire M.;Rycenga, Matthew;Zhou, Fei;Li, Zhi-Yuan;Xia, Younan
通讯作者：
Xia, Younan
影响因子：
56.9
作者：
Lim, Byungkwon;Jiang, Majiong;Xia, Younan
通讯作者：
Xia, Younan
影响因子：
3.7
作者：
Zhang, Qiang;Cobley, Claire M.;Zeng, Jie;Wen, Long-Ping;Chen, Jingyi;Xia, Younan
通讯作者：
Xia, Younan
影响因子：
4.3
作者：
Zhang, Qiang;Li, Weiyang;Wen, Long-Ping;Chen, Jingyi;Xia, Younan
通讯作者：
Xia, Younan
影响因子：
15
作者：
Lu, Xianmao;Tuan, Hsing-Yu;Xia, Younan
通讯作者：
Xia, Younan