High Density Novel Porous ZnO Nanosheets Based on a Microheater Chip for Ozone Sensors

High-density porous zinc oxide (ZnO) nanosheets (NSs) are grown on an aluminum (Al) substrate, and a porous ZnO NS-based microelectromechanical systems technology gas sensor is fabricated for ozone (O3) detection. The height of this new ZnO nanostructure can be controlled by using different thicknesses of an Al seedlayer ranging from 25 to 100 nm. Additionally, the results indicate that an increase in the ozone response depends on oxygen vacancy adsorption, as measured by photoluminescence emission. This paper resulted in a low-temperature, hydrothermally grown novel porous ZnO NS ozone gas sensor that measured O3 responses of 96.1% at 300 °C and 53.4% at 150 °C. The response of this sensor compared with the responses of other semiconductor metal oxide materials is also very significant, with the porous ZnO NSs showing potential applications in gas sensing devices used for environmental monitoring.