High sensitivity and anti-humidity gas sensor for nitrogen dioxide based on Ce/SnO2 nanomaterials

In this paper, the SnO2 and Ce/SnO2 nanomaterials are synthesized through a simple hydrothermal route and used for detecting NO2 gas. The SnO2 materials exhibit a good linearity for NO2 detection, and the limit of detection is calculated to be as low as about 5 ppb at 10% humidity. The humidity dependence of the gas sensing characteristics of metal oxide semiconductors has been one of the greatest obstacles for gas sensor applications. The NO2 gas sensing response of SnO2 and Ce/SnO2 also are investigated at 50% humidity. The Ce/SnO2 materials show higher response than pure SnO2. The gas sensing mechanism of Ce/SnO2 material is discussed in detailed. The reach results provide a new way for increasing the anti-humidity of the metal oxide semiconductor gas sensor.