Kang Yan, Tan Yinlong, Zhang Renyan, Xie Xiangnan, Hua Weihong
College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China.
College of Computer Science and Technology, National University of Defense Technology, Changsha 410073, China.
Nanomaterials (Basel). 2022 Oct 23;12(21):3725. doi: 10.3390/nano12213725.
As a promising topological insulator, two-dimensional (2D) bismuth selenide (BiSe) attracts extensive research interest. Controllable surface doping of layered BiSe becomes a crucial issue for the relevant applications. Here, we propose an efficient method for the chemical thinning and surface doping of layered BiSe, forming Se/BiSe heterostructures with tunable thickness ranging from a few nanometers to hundreds of nanometers. The thickness can be regulated by varying the reaction time and large-size few-layer BiSe sheets can be obtained. Different from previous liquid-exfoliation methods that require complex reaction process, in-situ and thickness-controllable exfoliation of large-size layered BiSe can be realized via the developed method. Additionally, the formation of Se nanomeshes coated on the BiSe sheets remarkably enhance the intensity of Raman vibration peaks, indicating that this method can be used for surface-enhanced Raman scattering. The proposed chemical thinning and surface-doping method is expected to be extended to other bulk-layered materials for high-efficient preparation of 2D heterostructures.
作为一种很有前景的拓扑绝缘体，二维（2D）硒化铋（BiSe）吸引了广泛的研究兴趣。层状BiSe的可控表面掺杂成为相关应用的关键问题。在此，我们提出了一种用于层状BiSe化学减薄和表面掺杂的有效方法，形成厚度可调范围从几纳米到几百纳米的Se/BiSe异质结构。厚度可以通过改变反应时间来调节，并且可以获得大尺寸的少层BiSe片材。与以往需要复杂反应过程的液体剥离方法不同，通过所开发的方法可以实现大尺寸层状BiSe的原位和厚度可控剥离。此外，涂覆在BiSe片材上的Se纳米网的形成显著增强了拉曼振动峰的强度，表明该方法可用于表面增强拉曼散射。所提出的化学减薄和表面掺杂方法有望扩展到其他体层材料，以高效制备二维异质结构。
