Highly sensitive, selective and stable NO2 gas sensors with a ppb-level detection limit on 2D-platinum diselenide films. Issue 14 (11th March 2020)

• Record Type: Journal Article
• Authors: Su, Teng-Yu; Chen, Yu-Ze; Wang, Yi-Chung; Tang, Shin-Yi; Shih, Yu-Chuan; Cheng, Faliang; Wang, Zhiming M.; Lin, Heh-Nan; Chueh, Yu-Lun
• Is Part Of: Journal of materials chemistry. Volume 8:Issue 14(2020)
• Page Start: 4851
• Page End: 4858
• Publication Date: 2020-03-11
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9tc05747a
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : High quality PtSe2 can be fabricated under 600 °C and has excellent NO2 sensitivity, which can reach sub ppb level. Abstract : Unlike common TMDCs such as MoS2, PtSe2 can be fabricated at temperatures below 600 °C, or even as low as 300 °C, while still maintaining high quality. By varying the selenization temperature from 300 °C to 600 °C, the electrical properties were changed significantly, resulting in superior gas sensing performance. Through comprehensive material analysis, an interesting phenomenon was found, namely that strain along the [001] direction existed in films grown at a low temperature rather than at a high temperature. Moreover, due to the layer-dependent property of PtSe2, a phase transition from metal-to-semiconductor occurs as the thickness is reduced. Hybridization of phase engineering and thermal strain engineering significantly enhances the gas sensing performance, resulting in PtSe2 with a dramatic increase in the response to 1 ppm NO2 from 25% to 550% once the thickness was reduced from 10 to 5 layers. In addition, PtSe2 showed good stability during exposure to not only 1 ppm but also 50 ppb NO2 for more than 5 cycles with responses of over 550% and 60%, respectively.