
283Carbon Nanotube–Based Electrochemical Biosensors
Aligned carbon
nanotube array
quartz
Removal of the
r
composite film
Sputter-coating
gold electrodes
Film casting
(i)(ii)
(i)
(ii)
(iv)
(iii)
Electrode
Electrode
60
Ethanol
Cyclohexane
50
40
30
20
10
0
0
5
10
15
20
25
0
0 200 400 600 800 1000
ppm
∆R (%
R (%)
1200 1400
240 480 720 960
Time (s)
1200 1440 1680
Resistance meter
Chemical
vapor
(1)
(2)
(3)
Polymer film
FIGURE 11.9
(a) Schematic illustration for (i) fabricating and (ii) characterizing the VA-CNT-polymer composite chemical vapor sensors. SEM images of the VA-MWNTs (iii) before
and (iv) after being partially coated with a polymer (PVAc) lm on top and t ...