New Design of ZnO Nanorod- and Nanowire-Based NO₂ Room-Temperature Sensors Prepared by Hydrothermal Method

Table 1

Response time/recovery time of the ZnO NR and NW sensors to various concentrations of NO₂ at different applied voltages.

Applied voltage	Nanorods			Nanowires
	1 ppm	5 ppm	10 ppm	1 ppm	2.5 ppm	5 ppm	10 ppm
1 V	270/716	466/827	293/553	181/1153	279/834	389/1238	441/535
2 V	547/498	608/800	277/786	131/202	141/302	108/216	43/136
4 V	11/187	843/1580	762/1597	321/-	305/734	248/712	298/600
8 V	547/416	708/917	668/1008	218/572	366/491	382/745	205/498

Unit: seconds.