School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore) http://www.ntu.edu.sg/home/hzhang/
Angew Chem Int Ed Engl. 2014 May 12;53(20):5083-7. doi: 10.1002/anie.201311309. Epub 2014 Apr 7.
Semiconducting nanosheets with microscale lateral size are attractive building blocks for the fabrication of electronic and optoelectronic devices. The phase-controlled chemical synthesis of semiconducting nanosheets is of particular interest, because their intriguing properties are not only related to their size and shape, but also phase-dependent. Herein, a facile method for the synthesis of phase-pure, microsized, two-dimensional (2D) CuSe nanosheets with an average thickness of approximately 5 nm is demonstrated. These hexagonal-phased CuSe nanosheets were transformed into cubic-phased Cu(2-x)Se nanosheets with the same morphology simply by treatment with heat in the presence of Cu(I) cations. The phase transformation, proposed to be a template-assisted process, can be extended to other systems, such as CuS and Cu1.97 S nanoplates. Our study offers a new method for the phase-controlled preparation of 2D nanomaterials, which are not readily accessible by conventional wet-chemical methods.
具有微尺度横向尺寸的半导体纳米片是制造电子和光电子器件的理想构建块。相控化学合成半导体纳米片特别有趣，因为它们的奇异性质不仅与其尺寸和形状有关，而且与相有关。在此，我们展示了一种简便的方法，可合成具有相纯度、微尺寸、二维（2D）的六边形相 CuSe 纳米片，其平均厚度约为 5nm。这些六角相的 CuSe 纳米片通过在存在 Cu（I）阳离子的情况下加热处理，很容易转化为具有相同形态的立方相 Cu（2-x）Se 纳米片。所提出的相转变是一种模板辅助过程，可以扩展到其他体系，如 CuS 和 Cu1.97S 纳米板。我们的研究为二维纳米材料的相控制备提供了一种新方法，这是传统湿化学方法不易实现的。
