SiC Foams Decorated with SnO2 Nanostructures for Room Temperature Gas Sensing.

Cell walls of the commercial silicon carbide (SiC)-based foams were decorated by one-dimensional tin dioxide (SnO₂) nanostructures. Thermal evaporation of SnO₂ powder with the assistance of a Au catalyst in inert atmosphere caused the formation of SnO₂ nanobelts on the pore surfaces. The room temperature ( RT) ammonia ( NH₃) and nitrogen dioxide ( NO₂) gas sensing behaviors were investigated systematically in both dry and humid air atmosphere with/without UV activation. The results were compared to those for bare SnO₂ and SiC. It was shown that SiC/SnO₂ composite was efficient to detect low concentration of NH₃ (10-50 ppm) and NO₂ (1-5 ppm) under humid air and UV activation at RT. [ABSTRACT FROM AUTHOR]