Zhang Wenli, Ma Zhuang, Wang Jing, Shao Bin, Zuo Xu
College of Electronic Information and Optical Engineering, Nankai University, Tianjin 300350, China.
School of Physics and Telecommunication Engineering, Zhoukou Normal University, Zhoukou 466001, China.
Phys Chem Chem Phys. 2024 Feb 14;26(7):6362-6371. doi: 10.1039/d3cp06002k.
Alpha-tellurene (α-Te), a two-dimensional (2D) material that has been theoretically predicted and experimentally verified, has garnered significant attention due to its unique properties. In this study, we investigated the 2D trilayer MoS/α-Te/WS van der Waals heterostructure with different stacking orders using first-principles calculations. Our results indicate that this heterotrilayer exhibits an intrinsic type-I band alignment and an indirect band gap similar to that of monolayer α-Te. Notably, the band edges of the heterostructure can be modulated by biaxial strain and an external electric field, enabling these edges to arise from different monolayers. This controlled manipulation facilitates the effective separation of photogenerated electron-hole pairs and prolongs the carrier lifetime. Moreover, the heterostructure can undergo a transition from an indirect to a direct band gap under biaxial compressive strain or a moderate negative electric field, and semiconductor-to-metal transition can also be achieved by intensifying the biaxial strain and external electric field. Overall, our research provides valuable theoretical insights into the potential applications of α-Te-based heterostructures, rendering them promising candidates for the next generation of nanodevices.
α-碲烯（α-Te）是一种已在理论上得到预测并经实验验证的二维材料，因其独特性质而备受关注。在本研究中，我们使用第一性原理计算研究了具有不同堆叠顺序的二维三层MoS/α-Te/WS范德华异质结构。我们的结果表明，这种异质三层结构呈现出本征I型能带排列以及与单层α-Te相似的间接带隙。值得注意的是，异质结构的能带边缘可通过双轴应变和外部电场进行调制，使得这些边缘来自不同的单层。这种可控操作有助于光生电子-空穴对的有效分离并延长载流子寿命。此外，在双轴压缩应变或适度负电场作用下，异质结构可从间接带隙转变为直接带隙，通过增强双轴应变和外部电场也可实现半导体到金属的转变。总体而言，我们的研究为基于α-Te的异质结构的潜在应用提供了有价值的理论见解，使其成为下一代纳米器件的有前景的候选材料。
