Surface Modification of Carbon Nanotube Networked Films with Au Nanoclusters for Enhanced NO₂ Gas Sensing Applications

Table 1

Comparison of the coefficient of variation, D (%) for three MWCNT-based gas sensors: (i) CNTs unfunctionalized, (ii) CNTs modified with Au loading of 5 nm, (iii) CNTs modified with Au loading of 10 nm, toward five gas exposures of individual gas of 1 and 10 ppm NO₂, 100 and 1000 ppm NH₃. The sensor temperature for all sensors is 200^°C. The thickness of MWCNTs is about 250–300 nm.

Gas concentration	Coefficient of variation, D (%)
	Sensor CNTs	Sensor CNTs_Au-5 m	Sensor CNTs_Au-10 m
1 ppm NO2	3.4	3.1	2.9
10 ppm NO2	14.1	1.2	3.0
100 ppm NH3	5.1	2.9	3.5
1000 ppm NH3	13.1	5.0	11.2