Few-layered α-MoTe2 Schottky junction for a high sensitivity chemical-vapour sensor

Iman Shackery, Atiye Pezeshki, Jae Young Park, Umadevi Palanivel, Hyeok Jae Kwon, Hyong Seo Yoon, Seongil Im, Jin Soo Cho, Seong Chan Jun

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

For the first time, we connect in series two α-MoTe2-based Schottky diodes (SDs) to form a back-to-back diode using the micromechanical exfoliation method. The α-MoTe2 SD exhibits an excellent ON/OFF current ratio of ∼103 and low-voltage operation at 5 V. Although various studies of α-MoTe2 field-effect transistors (FETs), phototransistors, and p-n diodes have been reported, there are no reported theoretical or experimental studies of α-MoTe2 for chemical sensing. Here, we experimentally assess the SD and a FET for gas sensing with exposure to different concentrations of NO2 and NH3. Interestingly, the α-MoTe2 SD showed a faster response and recovery time to NH3 and NO2 than the α-MoTe2 FET owing to its Schottky junction, which is favorable for detecting the Schottky-barrier height change due to gas exposure. The SD showed a fast response of 15 s when exposed to 70-ppb NO2 and ∼1 s when exposed to 70 ppb NH3 with a relative resistance change of 13% and 101%, respectively, and this was attributed to its physisorption process. In addition, our results are confirmed by density functional theory. The α-MoTe2-based SD is shown to be promising as an electrical rectifier or as a gas sensor owing to its simple and inexpensive electrical circuitry and excellent performance, including its low voltage, high ON/OFF current ratio and good sensitivity to toxic gases at room temperature. Further, it may be suitable for diverse uses, such as chemical and biosensing applications.

Original languageEnglish
Pages (from-to)10714-10722
Number of pages9
JournalJournal of Materials Chemistry C
Volume6
Issue number40
DOIs
Publication statusPublished - 2018 Jan 1

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Few-layered α-MoTe<sub>2</sub> Schottky junction for a high sensitivity chemical-vapour sensor'. Together they form a unique fingerprint.

  • Cite this

    Shackery, I., Pezeshki, A., Park, J. Y., Palanivel, U., Kwon, H. J., Yoon, H. S., Im, S., Cho, J. S., & Jun, S. C. (2018). Few-layered α-MoTe2 Schottky junction for a high sensitivity chemical-vapour sensor. Journal of Materials Chemistry C, 6(40), 10714-10722. https://doi.org/10.1039/c8tc02635a