High-Sensitivity Humidity Sensor Based on a Single SnO_2 Nanowire

摘要

We have synthesized high-yield SnO_2 NWs via a Au catalytic VLS growth process. CL characterization results demonstrate that the as-synthesized SnO_2 NWs possess a large number of oxygen vacancies in the crystals. Hence, the surface of the SnO_2 NW is very sensitive to oxygen and water vapor in air. As inspired by this, we fabricated a new type of SnO_2 humidity sensor based on a single NW. Both static and dynamic testing proved that the SnO_2 NW-based humidity sensor has a fast response and high sensitivity to RH changes in air, and at the same time, its response sensitivity is linear with RH in air. Considering excellent chemical stability of SnO_2, this new type of SnO_2 NW-based humidity sensor is expected to have promising applications in various complicated moisture, including acid and alkali moist gas for fast detecting of humidity.