Improving the hydrogen sensing properties of SnO2 nanowire-based conductometric sensors by Pd-decoration

Abstract

We fabricated bare and Pd-decorated SnO2 nanowires (NWs) for comparative study of hydrogen sensing. A selective vapor-liquid-solid method was used for fabricating SnO2 NWs and a UV reduction method was used to decorate Pd NPs on the surfaces of the fabricated NWs. Sensing studies showed that decorating the surfaces of SnO2 NWs with a noble metal increased the response to 1 ppm H-2 gas from 6.88 to 16.95 at an optimal working temperature of 300 degrees C. Furthermore, Pd decoration also increased the selectivity. The enhanced sensing properties of the Pd-decorated sensor are related to the Pd NPs' catalytic effect and the formation of Schottcky junctions. This study demonstrated the possibility of a high performance H-2 sensor created by combining metal oxide NWs with a catalyst such as Pd.