Fabrication and H-Sensing Properties of SnO Nanosheet Gas Sensors.

Vertically formed and well-defined SnO nanosheets are easy to fabricate, involving only a single process that is performed under moderate conditions. In this study, two different sizes of a SnO nanosheet were concurrently formed on a Pt interdigitated electrode chip, with interconnections between the two. As the SnO nanosheets were grown over time, the interconnections became stronger. The ability of the fabricated SnO nanosheets to sense H gas was evaluated in terms of the variation in their resistance. The resistance of a SnO nanosheet decreased with the introduction of H gas and returned to its initial level after the H gas was replaced with air. Also, the response-recovery behaviors were improved as a result of the growth of the SnO nanosheets owing to the presence of many reaction sites and strong interconnections, which may provide multipassages for the electron transfer channel, leading to the acceleration of the reaction between the H gas and SnO nanosheets.