Electronic Nose Based on Nanomaterials: Issues, Challenges, and Prospects

Table 1

EN based on different nanomaterials and their detection principle and target molecules.

Sr. number	Sensing material	Target	Principle	References
Single nanomaterial
1	SnO2 NB	Ethanol, isopropyl alcohol, toluene,	Chemiresistive	[83–86]
Multiple nanomaterial
2	Polypyrrole NTs	Helional gas	Chemiresistive	[176]
3	Polypyrrole NTs	Amyl butyrate	FET	[177]
4
5	SnO2 NWs	Ethanol, CO and 2-propanol	Chemiresistive	[87]
6	SnO2 NWs	Ethanol, Water	Chemiresistive	[178]
7	SnO2, In2O3, and TiO2 NWs	H2, CO	Chemiresistive	[179]
8	CNT	Eugenol, 2–4 DNT, heptanal	FET	[180]
9	CNT	Amyl butyrate, pentyl valerate (PV), butyl butyrate (BB), and propyl butyrate (PB)	FET	[181]
Nanomaterials film
10	ZnO NPs	Chinese liquors	Chemiresistive	[182]
11	SnO2 NPs + Ag/Pt	H2	Chemiresistive	[183]
12	Graphene	Amyl butyrate	FET	[109]
13	Au NPs	DNB, TNT, DNT	Chemiresistive	[184]
14	Diamond NPs	DNT, DMMP, NH3	SAW resonators	[185]
15	Si-NWs	Cancerous cells	chemiresistive	[186]
16	Si- NWs	TNT	FET	[187]
Nanocomposites
17	CNT + SnO2	Whiskey, methanol	Chemiresistive	[188]
18	PNC + CNT	Water, toluene	Chemiresistive	[189]
19	PNC	Lung cancer	Chemiresistive	[190]