Room Temperature Sensing Achieved by GaAs Nanowires and oCVD Polymer Coating

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Wang X., Ermez S., Goktas H., Gradecak S., Gleason K.

MACROMOLECULAR RAPID COMMUNICATIONS, cilt.38, sa.12, 2017 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 38 Sayı: 12
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1002/marc.201700055
  • Dergi Adı: MACROMOLECULAR RAPID COMMUNICATIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
  • Anahtar Kelimeler: conducting polymer, GaAs nanowires, gas detection, oCVD, CHEMICAL-VAPOR-DEPOSITION, CONDUCTING POLYMERS, CONJUGATED POLYMERS, GAS SENSORS, POLY(3,4-ETHYLENEDIOXYTHIOPHENE), FABRICATION, ARRAYS, FILMS
  • Ankara Üniversitesi Adresli: Hayır

Özet

Novel structures comprised of GaAs nanowire arrays conformally coated with conducting polymers (poly(3,4-ethylenedioxythiophene) (PEDOT) or poly(3,4-ethylenedioxythiophene-co-3-thiophene acetic acid) display both sensitivity and selectivity to a variety of volatile organic chemicals. A key feature is room temperature operation, so that neither a heater nor the power it would consume, is required. It is a distinct difference from traditional metal oxide sensors, which typically require elevated operational temperature. The GaAs nanowires are prepared directly via self-seeded metal-organic chemical deposition, and conducting polymers are deposited on GaAs nanowires using oxidative chemical vapor deposition (oCVD). The range of thickness for the oCVD layer is between 100 and 200 nm, which is controlled by changing the deposition time. X-ray diffraction analysis indicates an edge-on alignment of the crystalline structure of the PEDOT coating layer on GaAs nanowires. In addition, the positive correlation between the improvement of sensitivity and the increasing nanowire density is demonstrated. Furthermore, the effect of different oCVD coating materials is studied. The sensing mechanism is also discussed with studies considering both nanowire density and polymer types. Overall, the novel structure exhibits good sensitivity and selectivity in gas sensing, and provides a promising platform for future sensor design.