title: Electrical and gas sensing properties of polyaniline functionalized single-walled carbon nanotubes.
abstract: Electrical and gas sensing properties of single-walled carbon nanotube networks functionalized with polyaniline (PANI-SWNTs) were systematically investigated to understand the gas sensing mechanisms and optimize sensing performance. The temperature-dependent electrical resistance and field-effect transistor (FET) transfer characteristics indicated that the electrical properties of PANI-SWNTs are dominated by the PANI coating. The FET transfer characteristics of PANI-SWNTs exposed to different NH(3) concentrations indicated that the dominant sensing mechanism is the deprotonation of PANI by NH(3). Sensing experiments with different gas analytes revealed that PANI-SWNTs responded positively to NH(3), and negatively to NO(2) and H(2)S with sensitivities of 5.8% per ppm(v) of NH(3), 1.9% per ppm(v) of NO(2), and 3.6% per ppm(v) of H(2)S. The lower detection limits were 50, 500, and 500 ppb for NH(3), NO(2), and H(2)S, respectively.
authors.affiliation: Department of Chemical and Environmental Engineering and Center for Nanoscale Science and Engineering, University of California-Riverside, Riverside, CA 92521, USA.
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Lim
authors.forename: Nopparat
authors.initials: N
authors.lastname: Phiboolsirichit
authors.forename: Syed
authors.initials: S
authors.lastname: Mubeen
authors.forename: Marc A
authors.initials: MA
authors.lastname: Deshusses
authors.forename: Ashok
authors.initials: A
authors.lastname: Mulchandani
authors.forename: Nosang V
authors.initials: NV
authors.lastname: Myung
mesh_terms: D000641:Ammonia / Q000032:analysis; D000814:Aniline Compounds / Q000737:chemistry*; D017097:Electric Impedance; D004784:Environmental Monitoring / Q000379:methods; D005740:Gases / Q000032:analysis*; D018625:Microscopy, Atomic Force; D037742:Nanotubes, Carbon / Q000737:chemistry*; D013696:Temperature
chemical_list: D000814:Aniline Compounds; D005740:Gases; D037742:Nanotubes, Carbon; C416807:polyaniline; D000641:Ammonia