a1 Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210
CO-gas-sensing response of individual metal–oxide–metal (MOM) heterojunction nanowires (∼250 nm diameter) in the Au–NiO–Au system, where a nanoscale segment of NiO oxide (∼250 nm long) is sandwiched axially between Au nanowires, and between individual all-oxide NiO nanowires (∼250 nm diameter, ∼5 μm long), has been measured at 150 °C. While the all-oxide nanowires are highly resistive and show no measurable response, the MOM nanowires show ∼25% decrease in current with the introduction of 800 ppm CO. The response is reversible, but it is slow due to the low temperature used. MOM nanowires, by virtue of the nanoscale-dimension, low-resistance oxide segment and the high-quality “end-on” metal–oxide contact, are an attractive class of nanowire gas-sensing elements for potential use in multifunctional “bottom up” nanoelectronics.
(Received March 8 2008)
(Accepted May 15 2008)
1 This author was an editor of this journal during the review and decision stage. For the JMR policy on review and publication of manuscripts authored by editors, please refer to http://www.mrs.org/jmr_policy.