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A Photovoltaic Self-Powered Gas Sensor Based on All-Dry Transferred MoS₂ /GaSe Heterojunction for ppb-Level NO₂ Sensing at Room Temperature.

ABSTRACT: Traditional gas sensors are facing the challenge of low power consumption for future application in smart phones and wireless sensor platforms. To solve this problem, self-powered gas sensors are rapidly developed in recent years. However, all reported self-powered gas sensors are suffering from high limit of detection (LOD) toward NO₂ gas. In this work, a photovoltaic self-powered NO₂ gas sensor based on n-MoS₂ /p-GaSe heterojunction is successfully prepared by mechanical exfoliation and all-dry transfer method. Under 405 nm visible light illumination, the fabricated photovoltaic self-powered gas sensors show a significant response toward ppb-level NO₂ with short response and recovery time and high selectivity at room temperature (25 °C). It is worth mentioning that the LOD toward NO₂ of this device is 20 ppb, which is the lowest of the reported self-powered room-temperature gas sensors so far. The discussed devices can be used as building blocks to fabricate more functional Internet of things devices.

SUBMITTER: Niu Y

PROVIDER: S-EPMC8292907 | biostudies-literature |

REPOSITORIES: biostudies-literature

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