[2009月06月04日]

 

    最近,我组光伏电池研究工作在合成形貌可控的半导体材料方面取得新的进展(Rui Yu, Tong Ren, Keju Sun, Zhaochi Feng, Guanna Li and Can Li, 2009, The Journal of Physical Chemistry C,DOI: 10.1021/jp9025267)。

    可控合成具有特殊形貌的纳米粒子是当前科学研究的热点之一。电化学方法作为溶液化学合成方法中典型的方法之一,特别适合纳米粒子的可控合成。其中关键的挑战在于寻找合适的形貌控制介质,使其能够有效地在纳米粒子表面进行不同晶面上的选择性吸附。该工作首创性地发现,在电镀液中加入阳离子表面活性剂CTAB可以导致具有立方体结构的硒化亚铜单晶的生成。量化计算结果得出:Br-离子可以选择性的吸附在硒化亚铜{100}晶面上,从而有效降低硒化亚铜{100}晶面的表面能,达到合成具有单一立方体结构半导体材料的目的。这个工作的意义在于不仅为纳米立方体结构的硒化亚铜的应用提供了可能,同时为系统的研究形貌与催化活性之间的联系提供了途径。
 

Shape-Controlled Copper Selenide Nanocubes Synthesized by an Electrochemical Crystallization Method
Rui Yu, Tong Ren, Keju Sun, Zhaochi Feng, Guanna Li, Can Li*

J. Phys. Chem. C, 2009 in press

Communication. http://dx.doi.org/10.1021/jp9025267 

AbstractNanocubes of copper selenide (Cu2-xSe) have been synthesized through an electrochemical crystallization method using cetyltrimethylammonium bromide (CTAB) as the structure directing agent. The shapes of Cu2-xSe nanocubes can be controlled by the adsorption effect of CTA+ hydrocarbon chain and Br- ion on the facets of the Cu2-xSe crystals. First-principle quantum chemical calculations indicate that the preferential adsorption of bromide onto the {100} facets of Cu2-xSe crystals results in the final cubic shape. The ability to generate Cu2-xSe nanostructures with well-defined morphologies not only provides potential application of Cu2-xSe nanocubes in photoelectric devices but also provides a great opportunity to systematically study the relationship between their properties and geometric shapes.

 

Keywords:copper selenide, electrochemistry, crystal growth, electron microscopy, nanostructures