Self-powered photovoltaic photodetector established on lateral monolayer MoS2-WS2 heterostructures

• Published in: Nano energy 2018-09, Vol.51, p.45-53
• Main Authors: Wu, Wanhui, Zhang, Qi, Zhou, Xing, Li, Liang, Su, Jianwei, Wang, Fakun, Zhai, Tianyou
• Format: Article
• Language: English
• Subjects: Heterostructure; In-Plane; Monolayer; Photodetector; Self-powered
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2018.06.049

With the rapid development of modern semiconductor industry, power free or self-powered devices become an indispensable part in the electronic components and optoelectronic products. Epitaxial connected TMDs lateral heterojunctions with the maximum built-in potential at the hetero-interface offer fast separation of the photo-generated electron-hole (e-h) pairs without an external bias, which make them promising for self-powered devices. However, so far, the photovoltaic performance of such structures are rarely studied. Here, we report the photovoltaic light sensors based on individual monolayer MoS2-WS2 in-plane heterostructures that were created through a one-step synthesis strategy. The in situ second-harmonic generation (SHG) characterizations of this monolayer in-plane heterostructures directly demonstrate their underlying symmetry and high orientation. The photovoltaic photodetectors designed on individual MoS2-WS2 in-plane samples that operate in a self-powered mode (zero bias) exhibits a spectral responsivity (Rλ) of 4.36 mA/W and detectivity (D*) of 4.36 × 1013 Jones under 28.64 mW/cm2 @ 532 nm. The primary characteristics of the lateral heterostructure devices are attributed to the built-in potential at the interface. The initial self-powered light sensor in a monolayer heterostructures combined with the scalable growth can be further applied in other 2D heterostructures. We report the photovoltaic light sensors based on individual monolayer MoS2-WS2 in-plane heterostructures which exhibit a spectral responsivity (Rλ) of 4.36 mA/W and detectivity (D*) of 4.36 × 1013 Jones under 28.64 mW/cm2 @ 532 nm. [Display omitted] •High-quality MoS2-WS2 in-plane heterostructures were created by a one-step strategy;•The in-plane heterostructures demonstrate underlying symmetry and high orientation;•The photodetector based on the lateral heterostructures shows self-powered operation.