Jia Guozhi, Wu Zengna, Wang Peng, Yao Jianghong, Chang Kai
Tianjin Chengjian University, Tianjin 300384, China.
Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China.
Sci Rep. 2016 Feb 29;6:22191. doi: 10.1038/srep22191.
Bi2Se3 nanosheets were successfully synthesized by a microwave-assisted approach in the presence of polyvinylpyrroli done at a temperature of 180 °C for 2 h. The thin film was prepared on a silicon wafer via a self-deposition process in a Bi2Se3 nanosheet ink solution using the evaporation-induced self-assembly method. The structure and morphology of the obtained products were characterized by X-ray diffraction, scanning electron microscopy (SEM), x-ray photoelectron spectroscopy, and Raman spectroscopy. The highly uniform Bi2Se3 particles could be formed by controlling the oxygen plasma treatment time. After the plasma pretreatment from 10 to 20 s, the surface of Bi2Se3 film evolved from the worm-like structure to particles. The highly uniform thin film was formed on further increasing the plasma treatment time, which is consistent with the observed SEM results. Several important processes can result in the morphological evolution of Bi2Se3 nanosheets: (1) formation of Bi2Se3 oxide layer; (2) self-assembly of oxide nanoparticles under the action of high-energy oxygen plasma; and (3) electrostatic interaction and etching mechanism.
在180°C的温度下，于聚乙烯吡咯烷酮存在的条件下，通过微波辅助法成功合成了Bi2Se3纳米片，反应时长为2小时。采用蒸发诱导自组装法，在Bi2Se3纳米片油墨溶液中通过自沉积工艺在硅片上制备薄膜。通过X射线衍射、扫描电子显微镜（SEM）、X射线光电子能谱和拉曼光谱对所得产物的结构和形貌进行了表征。通过控制氧等离子体处理时间可以形成高度均匀的Bi2Se3颗粒。在等离子体预处理10至20秒后，Bi2Se3薄膜的表面从蠕虫状结构演变为颗粒状。进一步增加等离子体处理时间会形成高度均匀的薄膜，这与观察到的SEM结果一致。几个重要过程可导致Bi2Se3纳米片的形态演变：（1）Bi2Se3氧化层的形成；（2）在高能氧等离子体作用下氧化物纳米颗粒的自组装；（3）静电相互作用和蚀刻机制。
