New papers: Applied Physics Letters,101 (2012) 253106

Nguyen Van Hieu*, Phung Thi Hong Van, Le Tien Nhan, Nguyen Van Duy, Nguyen Duc Hoa, “Giant enhancement of H₂S gas response by decorating n-type SnO₂ nanowires with p-type NiO nanoparticles”, Applied Physics Letters,101 (2012) 253106

Abstract:Metal oxide nanowires (NWs) are widely considered as promising materials for gas sensor applications. Here, we demonstrate that by decorating NiO nanoparticles on SnO₂ NWs, the gas response to 10 ppm H₂S increased up to ~351-fold. The response of the NiO-decorated SnO₂ NWs sensor to 10 ppm H₂S at 300 °C reached ~1372, whereas the cross-gas responses to 5 ppm NH₃, 200 ppm C₂H₅OH, and 1 ppm NO₂ were negligible (1.8 to 2.9). The enhanced H₂S sensing performance was attributed by the catalytic effect of NiO and the formation of a continuous chain of n-p-n-p junctions.