Electrical properties of single and multiple poly(3,4-ethylenedioxythiophene) nanowires for sensing nitric oxide gas.
The electrical properties of conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), nanowires were studied to develop nitric oxide (NO) gas sensors with low working temperatures. A nanowire with a diameter of 300 nm was fabricated using dip-pen nanolithography (DPN) across a 55 microm gap between a pair of electrodes. The electrical properties of single or multiple PEDOT nanowires were examined by plotting the current-voltage (I-V) curves in the range -3 V to +3 V at temperatures between 298 K and 393 K. The conductance of parallel wires was normalized with respect to the dimensions of the fabricated nanowires. The single nanowire exhibited nonlinear conductance associated with hysteresis but multiple wires did not. The currents increased with the temperature and the I-V characteristics were consistent with the power law G(T)alphaT(alpha) with alpha approximately 5.14 and 5.43. The responses to NO were highly linear and reproducible, indicating that sensing using PEDOT nanowires was reliable with a minimal concentration of NO of 10 ppm.
Department of Electrical Engineering, National Taiwan University, Taipei, 10617, Taiwan.
Hui-Hsin
HH
Lu
Chia-Yu
CY
Lin
Tzu-Chien
TC
Hsiao
Yueh-Yuan
YY
Fang
Kuo-Chuan
KC
Ho
Dongfang
D
Yang
Chih-Kung
CK
Lee
Su-Ming
SM
Hsu
Chii-Wann
CW
Lin
D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D002138:Calibration; D004553:Electric Conductivity; D004563:Electrochemistry; D005740:Gases / Q000032:analysis* / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry*; D009569:Nitric Oxide / Q000032:analysis* / Q000737:chemistry*; D017711:Nonlinear Dynamics; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D013696:Temperature
D019086:Bridged Bicyclo Compounds, Heterocyclic; D005740:Gases; D011108:Polymers; C121383:poly(3,4-ethylene dioxythiophene); D009569:Nitric Oxide