Direct Measurement of Metal Surface Temperature During Catalytic Dissociation of Ozone for Sensor Application.

Temperature variation of a catalytic metal surface exposed to ozone produced in an atmospheric-pressure dielectric barrier discharge is examined by using a very thin thermocouple. The metal sheet is heated initially to a certain temperature ( T1) using a resistive heater and, then, the ozone concentration is increased with the heater current unchanged. When T1 is room temperature, the temperature of the metal sheet remains almost constant independent of ozone concentration. When T1 is increased up to 80 °C, the temperature of the metal sheet decreases clearly with increasing ozone concentration due to enhanced catalytic dissociation of ozone at the metal surface. The rate of decrease in temperature for a stainless steel sheet is increased from nearly 0% to $\sim 5.7$ % with increasing T1 from room temperature to 80 °C, while that for a platinum sheet is increased further to $\sim 17.5$ % at 80 °C due to stronger catalytic activity of platinum. The results confirm that the sensitivity for ozone is improved with a stronger catalytic metal heated to a higher temperature as the sensor body. [ABSTRACT FROM PUBLISHER]