P2.8.4 NO2 response to few-layers MoS2

Event

14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
Nürnberg/Nuremberg, Germany

Chapter

P2.8 Sensors Based on New Materials

Author(s)

C. Cantalini, L. Giancaterini - Department of Chemistry and Materials (Italy), M. Donarelli, S. Santucci, L. Ottaviano - Department of Physics Via Vetoio (Italy)

Pages

1656 - 1659

DOI

10.5162/IMCS2012/P2.8.4

ISBN

978-3-9813484-2-2

Price

free

Abstract

The gas sensing response to NO2 gas, H2 and CO of transition metal dichalcogenide (TMD) MoS2fewlayered structure, chemically exfoliated to obtain a suspension of 2D graphene-like MoS2 flakes and deposited by drop casting on Si3N4, is here presented.Films have been characterized by Raman, XPS Spectroscopy and SEM. Gas response to NO2 (20 ppb-1 ppm) and 25-200 C° operating temperature has shown a pto n-type change of the electrical response depending on the annealing temperature. The p to n inversion has been attributed to the formation of sulphur vacancies when annealing the as deposited MoS2in dry air at around 250 °C. MoS2 layered films have shown linear response of the electrical resistance in the gas concentration range 20 ppb - 1 ppm NO2and detection limit as low as 20 ppb at 200 °C operating temperature. This appears to be the first paper, to the best of our knowledge, reporting the sensing properties of 2D-MoSv to sub ppm concentrations of NO2 in dry air.