Table 1.

Comparison of NO₂ sensing properties of our Si NWs-based chemoresistive sensor with other sensors.

Sample	NO2 (ppm)	Temperature (°C)	Response time (s)	Recovery Time (s)	Ref.
Si NWs	2	115	75	300	This work
Cr2O3	3	200	-	-	[69]
Fe2O3	1	225	26	48	[70]
Cu:Fe2O3	5	300	85	105	[71]
α-Fe2O3	1	200	77	120	[72]
ZnO NRs/P-Si NWs	5	RT	800	780	[47]
Si NWs	0.01	40	-	-	[51]
ZnO NWs	2	200	1200	1200	[73]
In2O3	0.5	100–250	>170	>120	[74]
SnO	0.5	200	90	80	[75]
TeO2	10	RT	660	1200	[76]