Carbon Nanotubes as Active Components for Gas Sensors

Table 2

Summary of sensing performance of polymer functionalized CNT sensors. (Note: N/S = Not-stated.)

polymer	CNT type	Sensor configuration	Targeted analytes	Detection limit	Response time	Recovery time	Reference
PEI, Nafion	SWCNTs	FET	NO2, NH3	100 ppb NO2	∼1-2 min	N/S	[36]
PABS	SWCNTs	Resistor	NH3, NO2, H2O	20 ppb NO2, 100 ppb NH3	1–10 min	Several hours	[38]
PPy	SWCNTs	FET	NO2	N/S	N/S	∼2 h	[39]
PPy	S-SWCNT	FET	NO2, NH3	100 ppm NO2, 5 ppm NH3	N/S	N/S	[40]
PDPA	MWCNTs	Electrochemical gas sensor	CO	0.01 ppm	∼2 s	∼3 s	[41]
PMMA	MWCNTs	Resistor	dichloromethane, chloroform, acetone	N/S	2–5 s	∼10 s	[42]
Poly(3-methylthiophene)	MWCNTs	Resistor	CH2Cl2, CHCl3, CCl4, CH4	N/S	60 s	30–45 s	[43]
polystyrene	MWCNTs	Resistor	the good solvents of PS	N/S	<4 min	∼1 min	[44]
PEG	MWCNTs	Resistor	chloroform	N/S	<1 s	N/S	[45]
POAS	ACNTs	Resistor	HCl	100 ppm	N/S	N/S	[46]
poly(vinylacetate), polyisoprene, etc.	ACNTs	Resistor	Ethanol cyclohexane, tetrahydrofuran	N/S	<2 min	<2 min	[47]