Surface Acoustic Wave Sensors for Ammonia Detection at Room Temperature Based on SnO₂/Co₃O₄ Bilayers

Table 1

Sensitivity and limit of detection.

SAW sensor	NH3		Methanol		Toluene
	Sensitivity (Hz/ppm)	LOD (ppm)	Sensitivity (Hz/ppm)	LOD (ppm)	Sensitivity (Hz/ppm)	LOD (ppm)
S1	2.00	15	0.83	36	0.50	60
S2	3.33	9	1.33	23	0.60	50

: frequency change and : analyte gas concentration for the two sensitive films.