Room temperature detection of NO₂ using InSb nanowire

Room temperature detection of NO₂ down to one part-per-million (ppm) using single crystalline n-type InSb nanowires (NWs) chemiresistive gas sensor is presented. These sensors were synthesized and fabricated by the combination of chemical vapor deposition and dielectrophoresis alignment techniques. The sensor devices showed an increase in resistance upon exposure to successive increments of NO₂ concentration up to 10 ppm. The reduction in conductance of n-type InSb NWs when exposed to NO₂ is made possible due to the charge transfer from the InSb NW surface to the adsorbed electron acceptor NO₂ molecules. The demonstrated results suggest InSb NW as a promising candidate in sensing applications as well as being environmental friendly over existing arsenic and/or phosphorous-based III-V NW sensors.