Table 1: Summary of gas-sensing performance of pristine CNT gas sensors. (Note: N/S = Not-stated.)

CNT typeSensor configurationTargeted analytesDetection limitResponse timeRecovery timeReference

S-SWCNTFETNO2, NH32 ppm NO2, 0.1% NH3<10 min 1 h C)[7]
SWCNTsResistorNO2, Nitrotoluene44 ppb NO2, 262 ppb Nitrotoluene10 min10 min (UV)[14]
SWCNTsResistorNH35 ppm 10 min 20 min C)[16]
SWCNTsResistorNH35 ppm 10 min 10 min C)[17]
MWCNTsCapacitor and ResistorNH310 ppm2-3 minseveral days C in vacuum)[18]
MWCNTsResistorNH32500 ppmN/SN/S[19]
MWCNTsFETNO250 ppm 500 s 10 min (10 V bias potential)[20]
MWCNTsResistorSO2, HF10 ppm SO2, 4 ppm HFN/SN/S[21]
MWCNTsElectrochemical Gas sensorCl2100 ppm 150 s 150 s[22]
ACNTsResistorNO210 ppb 60 min 60 min C)[26]
ACNTsResistorNO210 ppmN/SN/S[27]
ACNTsResistorNO, NO22 ppm NO, 2 ppm NO2N/S 20 min C and UV)[28]
ACNTsResistorNH3 0.1%N/SN/S[29]
ACNTsFETN250 mTorrN/SN/S[30]