Catalytically modified Pt/Catalysed TiO2/SiC devices for hydrogen and hydrocarbon gas sensing

In this paper the hydrogen and hydrocarbon gas sensing performance of the Pt/Catalysed TiO2/SiC devices have been studied. The TiO2 metal oxide thin films were catalytically modified employing Pt and Pd. The electrical properties of the fabricated devices were studied by measuring their capacitance-voltage (C-V), conductance-voltage (G-V) and dynamic response characteristics. The sensor's response as a function of operating temperature (25 degrees C to 700 degrees C) and concentrations less than 1% of the analyte gases have been investigated. The sensitivity of the Pt catalysed TiO2 sensor was found to be superior when compared to TiO2 catalysed with Pd. A voltage shift of 3.2V for 1% propene at 420 degrees C and 2.8V for 1% hydrogen at 250 degrees C in an ambient containing synthetic air was recorded for the Pt catalysed TiO2 sensor. The response of Pt catalysed TiO2 sensor was found to be approximately 4 times larger when compared to the non catalysed counterpart.