Phase-Controlled Growth of 1T'-MoS 2 Nanoribbons on 1H-MoS 2 Nanosheets.

Two-dimensional (2D) heterostructures are emerging as alternatives to conventional semiconductors, such as silicon, germanium, and gallium nitride, for next-generation electronics and optoelectronics owing to their ultrathin thickness, absence of dangling bonds, and strong light-matter interaction. However, the direct growth of 2D heterostructures, especially for those with metastable phases still remains challenging. To obtain 2D transition metal dichalcogenides (TMDs) with designed phases, it is highly desired to develop phase-controlled synthetic strategies. Here, a facile chemical vapor deposition (CVD) method is reported to prepare vertical 1H/1T' MoS 2 heterophase structures. By simply changing the growth atmosphere, semi-metallic 1T'-MoS 2 can be in-situ grown on the top of semiconducting 1H-MoS 2 , forming vertical semiconductor/semi-metal 1H/1T' heterophase structures with a sharp interface. The integrated device based on the 1H/1T' MoS 2 heterophase structure displays a typical rectifying behavior with a current rectifying ratio of ∼10 3 . Moreover, the 1H/1T' MoS 2 -based photodetector achieves a responsivity of 1.07 A/W at 532 nm with an ultra-low dark current of less than 10 -11 A. The aforementioned results indicate that 1H/1T' MoS 2 heterophase structures could be a promising candidate for the future rectifiers and photodetectors. Importantly, our approach might pave the way toward tailoring the phases of TMDs, which can help us understand and utilize phase engineering strategies to promote the performance of electronic devices. This article is protected by copyright. All rights reserved.