Nanocrystalline Metal Oxides for Methane Sensors: Role of Noble Metals

Table 1

The sensing results of the planar structures at 𝟕𝟎^∘𝐂 and MIM structures at 𝟏𝟎𝟎^∘𝐂 for different concentrations of methane using nitrogen and synthetic air as carrier gases.

% CH4	Response				Response time (s)				Recovery time (s)
	Planar		MIM		Planar		MIM		Planar		MIM
	Nitrogen	Synthetic air	Nitrogen	Synthetic air	Nitrogen	Synthetic air	Nitrogen	Synthetic air	Nitrogen	Synthetic air	Nitrogen	Synthetic air
0.01	21.2	9.2	18.2	6.5	16.2	19.2	10.2	13.2	33.2	34.2	18.7	20.3
0.05	25.4	14.6	22.3	11.4	13.3	17.4	6.7	9.3	30.3	32.8	17.2	19.2
0.1	39.3	18.3	23.2	16.8	11.1	16.4	6.03	8.2	27.5	29.6	16.8	17.3
0.5	42.2	21.6	25.2	17.2	8.4	15.2	4.02	6.9	25.7	27.4	16.1	17.1
1	47.5	25.7	32.2	20.4	4.6	12.6	2.69	4.2	22.7	23.4	16.0	16.2