Branched SnO2 nanowires on metallic nanowire backbones for ethanol sensors application

We report the synthesis of hierarchically branched semiconducting SnO2 nanowire on metallic Sb-doped SnO2 nanowires by the sequential seeding of multiple nanowire generations with Au nanoparticles as catalysts. Such semiconducting nanowire/metallic backbone complex structures increase the potential functionality of SnO2 nanowires. Branched SnO2 nanowire films are used as sensing materials for high-performance ethanol sensor fabrication. The nanowire sensors show sub-ppm sensitivity and fast response and recovery times at 300°C. A linear equation relationship between sensitivity and the ethanol vapor concentration was observed.