Detection Characteristics for the Ultra Lean NOx Gas Concentration Using the MWCNT Gas Sensor Structured with MOS-FET

MOS-FET 구조의 MWCNT 가스센서를 이용한 초희박 NOx 가스 검출 특성

  • Received : 2013.08.18
  • Accepted : 2013.08.23
  • Published : 2013.09.01


Carbon nanotubes(CNT) has strength and chemical stability, greatly conductivity characteristics. In particular, MWCNT (multi-walled carbon nanotubes) show rapidly resistance sensitive for changes in the ambient gas, and therefore they are ideal materials to gas sensor. So, we fabricated NOx gas sensors structured MOS-FET using MWCNT (multi-walled carbon nanotubes) material. We investigate the change resistance of NOx gas sensors based on MOS-FET with ultra lean NOx gas concentrations absorption. And NOx gas sensors show sensitivity on the change of gate-source voltage ($V_{gs}=0[V]$ or $V_{gs}=3.5[V]$). The gas sensors show the increase of sensitivity with increasing the temperature (largest value at $40^{\circ}C$). On the other hand, the sensitivity of sensors decreased with increasing of NOx gas concentration. In addition, We obtained the adsorption energy($U_a$), $U_a$ = 0.06714[eV] at the NOx gas concentration of 8[ppm], $U_a$ = 0.06769[eV] at 16[ppm], $U_a$ = 0.06847[eV] at 24[ppm] and $U_a$ = 0.06842[eV] at 32[ppm], of NOx gas molecules concentration on the MWCNT gas sensors surface with using the Arrhenius plots. As a result, the saturation phenomena is occurred by NOx gas injection of concentration for 32[ppm].


MWCNT (multi-walled carbon nano tube);MOS-FET;NOx Gas sensor;Ultra lean concentrations


  1. J. G. Kim, S. C. Kang, E. J. Shin, D. Y. Kim, J. H. Lee, and Y. S. Lee, Appl. Chem. Eng., 23, 47 (2012).
  2. P. S. Su and T. T. Pan, Mat. Chem. Phys., 125, 351 (2001).
  3. S. H. Lee and J. S. Im, S. C. Kang, and T. S. Bae, Chem. Phys. Lett., 497, 191 (2010).
  4. J. G. Park and K. J. Lee, J. Kor. Inst. Met. & Mater., 13, 38 (2000).
  5. G. Wiegleb and J. Heitbaum, Sens. Act. B, 17, 93 (1994).
  6. D. E. Williams, Sens. Act. B, 57, 1 (1999).
  7. E. H. Espinosa, R. Ionescu, C. Bittencourt, A. Felten, R. Erni, G. Van Tendeloo, J. J. Pireaux, and E. Llobet, Thin Solid Films, 515, 8322 (2007).
  8. T. Ueda, S. Katsuki, N. Heidari Abhari, T. Ikegami, F. Mitsugi, and T. Nakamiya. Surf. Coat. Technol., 520, 5325 (2008).
  9. H. S. Kim and K. U. Jang, J. KIEEME, 26, 325 (2013).
  10. W. J. Lee, M. K. Choi, and K. U. Jang, J. KSDIT, 11, 55 (2012).
  11. A. Afzal, N. Cioffi, L. Sabbatini, and L. Torsi, Sensor and Act. B, 171, 25 (2012).
  12. M. K. Kwon and Y. T. Hong, J. KIEEME, 22, 38 (2009).
  13. B. C. Yadav, Satyendra Single, and Anuradha Yadav, Appl. Surface. Sci., 257, 1960 (2011).
  14. G. Chakraborty, K. Gupta, A. K. Meikap, R. Babu, and W. J. Blau, Solid State Comm., 152, 13 (2012).


Supported by : 가천대학교