Journal Article

MoS2 Nanosheets Sensitized with Quantum Dots for Room-Temperature Gas Sensors

Zhang, Yuzhu, Tang, Jiang, Yi, Fei, Liu, Huan, Hua-Yao, Li, Tian Zhilai, Hu, Zhixiang, Gao Naibo, Zhou, Licheng, Zhang, Baohui, Zhang, Jianbing, Liu Jingyao

2020

Overview

HighlightsHighly sensitive and selective room-temperature NO2 gas sensors by sensitizing MoS2 nanosheets with PbS quantum dots were demonstrated. In this device architecture, the receptor and transduction function as well as the utility factor of semiconductor gas sensors could be enhanced simultaneously.The strategy of sensitizing 2D semiconductors with quantum dots as sensitive and selective receptors for gas molecules may offer a powerful new degree of freedom to the surface and interface engineering of semiconductor gas sensors.The Internet of things for environment monitoring requires high performance with low power-consumption gas sensors which could be easily integrated into large-scale sensor network. While semiconductor gas sensors have many advantages such as excellent sensitivity and low cost, their application is limited by their high operating temperature. Two-dimensional (2D) layered materials, typically molybdenum disulfide (MoS2) nanosheets, are emerging as promising gas-sensing materials candidates owing to their abundant edge sites and high in-plane carrier mobility. This work aims to overcome the sluggish and weak response as well as incomplete recovery of MoS2 gas sensors at room temperature by sensitizing MoS2 nanosheets with PbS quantum dots (QDs). The huge amount of surface dangling bonds of QDs enables them to be ideal receptors for gas molecules. The sensitized MoS2 gas sensor exhibited fast and recoverable response when operated at room temperature, and the limit of NO2 detection was estimated to be 94 ppb. The strategy of sensitizing 2D nanosheets with sensitive QD receptors may enhance receptor and transducer functions as well as the utility factor that determine the sensor performance, offering a powerful new degree of freedom to the surface and interface engineering of semiconductor gas sensors.

• Publisher: Springer Nature B.V
• Subject: Carrier mobility / Computer architecture / Degrees of freedom / Environmental monitoring / Gas sensors / Internet of Things / Layered materials / Lead sulfides / Molybdenum disulfide / Nanosheets / Nitrogen dioxide / Operating temperature / Power consumption / Quantum dots / Receptors / Room temperature / Sensitizing / Sensors