A study on detecting amine gas using chemical characterization of Ag nanowire

Silver nanowires with diameters ranging from 150 to 200 nm and lengths of 20 ~ 4 or more were prepared by synthesizing in solution-phase. After preparing Ag nanowires, we removed PVP on the surface of Ag nanowires. The methods to remove PVP are followed. We stirred Ag nanowires / 5M HNO₃ solutions for 30 minutes. This method makes PVP on an Ag nanowire surface be etched and corroded. Next, we made the nanosized chemical gas sensor using an Ag nanowire between two electrodes on the silicon substrate to use DEP force. Upon exposure to ammonia(NH3) vapor, ensembles of these Ag nanowires showed a resistance increase, that was large, fast and reversible. The reason is that the PVP on the surface of Ag nanowires are removed. These PVP have played role in protecting from by ammonia(NH3) vapor. After removing PVP, the corrosion parts are made on the surface of Ag nanowire. These corrosion parts on an Ag nanowire surface respond with NHj vapor in the air. We guess that this chemical responding is influenced by some reasons, which interrupt electron´s transfer through an Ag nanowire backbone. However, more data will be needed in order to unambiguously reveal the structure and chemical composition.