A Single Nanobelt Transistor for Gas Identification: Using a Gas-Dielectric Strategy

Abstract

Despite tremendous potential and urgent demand in high-response low-cost gas identification, the development of gas identification based on a metal oxide semiconductor nanowire/nanobelt remains limited by fabrication complexity and redundant signals. Researchers have shown a multisensor-array strategy with “one key to one lock” configuration. Here, we describe a new strategy to create high-response room-temperature gas identification by employing gas as dielectric. This enables gas discrimination down to the part per billion (ppb) level only based on one pristine single nanobelt transistor, with the excellent average Mahalanobis distance (MD) as high as 35 at the linear discriminant analysis (LDA) space. The single device realizes the selective recognition function of electronic nose. The effect of the gas dielectric on the response of the multiple field-effect parameters is discussed by the comparative investigation of gas and solid-dielectric devices and the studies on trap density changes in the conductive channel. The current work opens up exciting opportunities for room-temperature gas recognition based on the pristine single device.

Interpenetrating Polymer Semiconductor Nanonetwork Channel for Ultrasensitive, Selective, and Fast Recovered Chemodetection

“…However, when the NH 2 -IPSN-based FET was exposed to 100 ppm SO 2 , the responsivity (64%) was much smaller than that to 5 ppm NO 2 (2193%), even though SO 2 gas exhibits electron-donating nature, which is similar to NO 2 . This result is mainly attributed to the difference in electron affinity between SO 2 and NO 2 ; NO 2 gas, which has stronger electron affinity (2.27 eV), can induce more efficient charge transfer than SO 2 (1.11 eV) (Figure b). , Additionally, the NH 2 -IPSN-based FET did not respond noticeably to reducing gases (H 2 S and NH 3 ) with negative electron affinity (−1.16 and −2.0 eV, respectively). , This is because the reducing gases exhibit electron-donating nature, which is equivalent to inherent electrical property of the NH 2 groups, so that charge transfer between the molecules is not supposed to develop significantly. All the devices showed negligible responsivity to the nonpolar gas hexane, even at the highest concentration of 1000 ppm, because hexane could not induce charge transfer in PDPP-DTT.…”

“…59,60 Additionally, the NH 2 -IPSN-based FET did not respond noticeably to reducing gases (H 2 S and NH 3 ) with negative electron affinity (−1.16 and −2.0 eV, respectively). 61,62 This is because the reducing gases exhibit electron-donating nature, which is equivalent to inherent electrical property of the NH 2 groups, so that charge transfer between the molecules is not supposed to develop significantly. All the devices showed negligible responsivity to the nonpolar gas hexane, even at the highest concentration of 1000 ppm, because hexane could not induce charge transfer in PDPP-DTT.…”