Research Article

Unexpected Selectivity of UV Light Activated Metal-Oxide-Semiconductor Gas Sensors by Two Different Redox Processes

Figure 3

Current responses of the ZnO film sensor to acetone vapor under UV irradiation: (a) current response before annealing under 20°C and 45% relative humidity. (b) Current response before annealing under 22°C and 55% relative humidity. (c) Current response after annealing under 20°C and 45% relative humidity. (d) Current response after annealing under 22°C and 55% relative humidity. The solid arrows mark the injection of RA and dashed arrows the injection of nitrogen, serving as a nonreactive gas.
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