Ultrahigh ethanol response of SnO2 nanorods at low working temperature arising from La2O3 loading

The influences of La2O3 loading on the ethanol sensing properties of SnO2 nanorods were investigated. An obvious enhancement of response was obtained. The response of 5 wt% La2O3 loaded SnO2 nanorods was up to 213 for 100 ppm ethanol at low working temperature of 200 °C, while that of pure SnO2 nanorods is 45.1. The improvement in response might be attributed to the presence of basic sites, which facilitated the dehydrogenation process. While the working temperature was increased to 300 °C, the sensor response decreased to 16 for 100 ppm ethanol. Additionally, the La2O3 loaded SnO2 nanorods sensors showed good selectivity to ethanol over methane and hydrogen. Our results demonstrated that the La2O3 loaded SnO2 nanorods were promising in fabricating high performance ethanol sensors which could work at low temperature.