| Popis: |
Highly porous pure and noble metal (Ag, PdAg and Pd) doped ZnO nanostructures were fabricated by pulsed laser deposition (PLD) in air at atmospheric pressure (in open air). This technology leads to the formation of nanostructures composed of nanoparticles or nanoaggregates. The as-deposited nanostructures possess a large surface-to-volume ratio, which makes them suitable for gas-sensor applications. In this work, we demonstrated the response of pure ZnO and of Ag-ZnO, Pd-ZnO and PdAg-ZnO sensor elements to NH3, CO, ethanol, and acetone exposure under UV light irradiation. The effect was studied of simultaneous UV and red or green light irradiation on the sensor element’s response, selectivity, and response and recovery time. It was found that irradiation by UV and red light has the effect of improving the Ag-ZnO sensor’s response to CO exposure and suppressing its response to NH3, ethanol and acetone. The same behavior was exhibited by the pure ZnO sensor element irradiated simultaneously by UV and green light. |
