Kong Delin, Tian Feng, Xu Yingying, Zhu Shaoqun, Yu Zetong, Xiong Lefeng, Li Peipei, Wei Huiyun, Zheng Xinhe, Peng Mingzeng
Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, No. 30, Xueyuan Road, Beijing 100083, China.
Phys Chem Chem Phys. 2023 Nov 15;25(44):30361-30372. doi: 10.1039/d3cp02137h.
Beyond three-dimensional (3D) architectures, polar semiconductor heterostructures are developing in the direction of two-dimensional (2D) scale with mix-dimensional integration for novel properties and multifunctional applications. Herein, we stacked 2D Janus MoSSe and 3D wurtzite GaN polar semiconductors to construct MoSSe/GaN polar heterostructures by polarity configurations. The structural stability was enhanced as binding energy changed from -0.08 eV/-0.17 eV in the N polarity to -0.24 eV/-0.42 eV in the Ga polarity. In particular, the polarity reversal of GaN in contact with Janus MoSSe not only determined the charge transfer direction but also significantly increased the electrostatic potential difference from 0.71 eV/0.78 eV in the N polarity to 3.13 eV/2.24 eV in the Ga polarity. In addition, strain modulation was further utilized to enhance interfacial polarization and tune the electronic energy band profiles of Janus MoSSe/GaN polar heterostructures. By applying in-plane biaxial strains, the AA and AA' polarity configurations induced band alignment transition from type I (tensile) to type II (compressive). As a result, both the polarity reversal and strain modulation provide effective ways for the multifunctional manipulation and facile design of Janus MoSSe/III-nitrides polar heterostructures, which broaden the Janus 2D/3D polar semiconducting devices in advanced electronics, optoelectronics, and energy harvesting applications.
除了三维（3D）结构外，极性半导体异质结构正朝着二维（2D）尺度发展，并通过混合维度集成实现新颖特性和多功能应用。在此，我们堆叠二维Janus MoSSe和三维纤锌矿GaN极性半导体，通过极性配置构建MoSSe/GaN极性异质结构。随着结合能从N极性的-0.08 eV/-0.17 eV变为Ga极性的-0.24 eV/-0.42 eV，结构稳定性得到增强。特别地，与Janus MoSSe接触的GaN的极性反转不仅决定了电荷转移方向，还显著增加了静电势差，从N极性的0.71 eV/0.78 eV增加到Ga极性的3.13 eV/2.24 eV。此外，进一步利用应变调制来增强界面极化并调整Janus MoSSe/GaN极性异质结构的电子能带分布。通过施加面内双轴应变，AA和AA'极性配置导致能带排列从I型（拉伸）转变为II型（压缩）。结果，极性反转和应变调制都为Janus MoSSe/III族氮化物极性异质结构的多功能操纵和简便设计提供了有效途径，这拓宽了Janus二维/三维极性半导体器件在先进电子、光电子和能量收集应用中的应用范围。
