Ge/MoS₂van der Waals heterostructure enables bias-dependent selective detection of visible and near infrared.

Highly sensitive and system integrable gas sensors play a significant role in industry and daily life, and MoS₂ has emerged as one of the most promising two-dimensional nanomaterials for gas sensor technology. In this study, we demonstrate a scalable and monolithically integrated active-matrix gas sensor array based on large-area bilayer MoS₂ films synthesized via two-successive steps: radio-frequency magnetron sputtering and thermal sulfurization. The fabricated thin-film transistors exhibit consistent electrical performance over a few centimeters area and resulting gas sensors detect NO₂ with ultra-high sensitivity across a wide detection range, from 1 to 256 ppm. This is due to the abundant grain boundaries of the sputtered MoS₂ channel, which perform as active sites for absorption of NO₂ gas molecules. The demonstrated active-matrix gas sensor arrays display good switching capabilities and are anticipated to be readily integrated with additional circuitry for different gas sensing and monitoring applications.