Department of Chemistry, Oregon State University, Corvallis, OR 97331-4003.
Proc Natl Acad Sci U S A. 2013 Nov 12;110(46):18397-401. doi: 10.1073/pnas.1315396110. Epub 2013 Oct 28.
The selective synthesis and in situ characterization of aqueous Al-containing clusters is a long-standing challenge. We report a newly developed integrated platform that combines (i) a selective, atom-economical, step-economical, scalable synthesis of Al-containing nanoclusters in water via precision electrolysis with strict pH control and (ii) an improved femtosecond stimulated Raman spectroscopic method covering a broad spectral range of ca. 350-1,400 cm(-1) with high sensitivity, aided by ab initio computations, to elucidate Al aqueous cluster structures and formation mechanisms in real time. Using this platform, a unique view of flat Al13(μ3-OH)6(μ2-OH)18(H2O)2415 nanocluster formation is observed in water, in which three distinct reaction stages are identified. The initial stage involves the formation of an Al7(μ3-OH)6(μ2-OH)6(H2O)12 cluster core as an important intermediate toward the flat Al13 aqueous cluster.
在水中选择性合成和原位表征含铝簇是一个长期存在的挑战。我们报告了一种新开发的集成平台，该平台结合了（i）通过精确电解在严格的 pH 控制下在水中选择性、原子经济性、步骤经济性、可扩展性合成含铝纳米簇，以及（ii）改进的飞秒受激拉曼光谱法，该方法覆盖约 350-1400 cm(-1) 的宽光谱范围，灵敏度高，辅以从头算计算，可实时阐明 Al 水溶液簇结构和形成机制。使用该平台，在水中观察到独特的平面Al13(μ3-OH)6(μ2-OH)18(H2O)2415纳米簇形成的视图，其中确定了三个不同的反应阶段。初始阶段涉及形成作为平面 Al13 水溶液簇的重要中间体的Al7(μ3-OH)6(μ2-OH)6(H2O)12簇核。
