Abstract
A new single nanowire based nanosensor is demonstrated for illustrating its ultrahigh sensitivity for gas sensing. The device is composed of a single ZnO nanowire mounted on Pt electrodes with one end in Ohmic contact and the other end in Schottky contact. The Schottky contact functions as a "gate" that controls the current flowing through the entire system. By tuning the Schottky barrier height through the responsive variation of the surface chemisorbed gases and the amplification role played by the nanowire to Schottky barrier effect, an ultrahigh sensitivity of 32 000% was achieved using the Schottky contacted device operated in reverse bias mode at 275 °C for detection of 400 ppm CO, which is 4 orders of magnitude higher than that obtained using an Ohmic contact device under the same conditions. In addition, the response time and reset time have been shortened by a factor of 7. The methodology and principle illustrated in the paper present a new sensing mechanism that can be readily and extensively applied to other gas sensing systems. © 2009 American Chemical Society.
Original language | English (US) |
---|---|
Pages (from-to) | 17690-17695 |
Number of pages | 6 |
Journal | Journal of the American Chemical Society |
Volume | 131 |
Issue number | 48 |
DOIs | |
State | Published - Dec 9 2009 |
Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: This research was supported by DARPA (Army/AMCOM/REDSTONE AR, W31P4Q-08-01-0009), BES DOE (DE-FG02-07ER46394), the Air Force Office (FA9550-081-0446), DARPA/ARO W911NF-08-1-0249, the KAUST Global Research Partnership, and NSF (DMS 0706436, CMMI 0403671). The financial support provided by the National Science Council of the Republic of China (Taiwan) under Grants NSC-98-2221-E-007034-MY3 (S.-Y.L.), NSC97-2917-1-007-108 (T.-Y.W.), and NSC982112-M-032-003-MY3 (P.-H.Y.) is also greatly appreciated. We also thank Dr. Qin Kuang for setting up the gas sensor measurement system.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.