Improvement in Chemiresistive Response of SnO2 Thin Film by RuO2-Nanosheets-Functionalization and Its Application to Highly Sensitive Ethanol Sensor

This paper introduces the use of ruthenium dioxide (RuO 2 ) nanosheets as a catalyst in gas sensors, significantly enhancing the chemiresistive response of tin dioxide (SnO 2 ) thin films for ethanol detection. The RuO 2 -functionalized device, integrated with a microheater for low-power operation, demonstrates a 243% improved response to 10 ppm ethanol compared to that of pristine SnO 2 . The sensor is operable at 250 ℃ with 18 mW power and fabricated with bulk-micromachining, thus these could be suitable for portable applications. Additionally, the sensor's performance at exposure to ethanol at various concentrations down to 500 ppb is characterized.