State Key Laboratory of Material Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China.
School of Physics, Huazhong University of Science and Technology (HUST), Wuhan, 430074, P. R. China.
Small. 2018 Feb;14(7). doi: 10.1002/smll.201702731. Epub 2018 Jan 10.
The important role of p-n junction in modulation of the optoelectronic properties of semiconductors is widely cognized. In this work, for the first time the synthesis of p-GaSe/n-MoS heterostructures via van der Waals expitaxial growth is reported, although a considerable lattice mismatching of ≈18% exists. According to the simulation, a significant type II p-n junction barrier located at the interface is expected to be formed, which can modulate optoelectronic properties of MoS effectively. It is intriguing to reveal that the presence of GaSe can result in obvious Raman and photoluminescence (PL) shift of MoS compared to that of pristine one, more interestingly, for PL peak shift, the effect of GaSe-induced tensile strain on MoS has overcome the p-doping effect of GaSe, evidencing the strong interlayer coupling between GaSe and MoS . As a result, the photoresponse rate of heterostructures is improved by almost three orders of magnitude compared with that of pristine MoS .
p-n 结在调制半导体的光电性能方面的重要作用已被广泛认知。在这项工作中，首次通过范德华外延生长报告了 p-GaSe/n-MoS 异质结构的合成，尽管存在约 18%的相当大的晶格失配。根据模拟，预计将在界面处形成显著的 II 型 p-n 结势垒，这可以有效地调制 MoS 的光电性能。有趣的是，与原始 MoS 相比，GaSe 的存在导致 MoS 的拉曼和光致发光（PL）明显移动，更有趣的是，对于 PL 峰移动，GaSe 引起的张应变对 MoS 的影响克服了 GaSe 的 p 掺杂效应，证明了 GaSe 和 MoS 之间的强层间耦合。因此，与原始 MoS 相比，异质结构的光响应率提高了近三个数量级。
