“…It is revealed that the responses of sensors toward NO 2 , acetone, ethanol, methanol, toluene, trimethylamine and NH 3 are 2.5%, 2.3%, 1.5%, 3%, 3.5%, 3% and 98% respectively, which indicate that the sensors exhibit good selectivity to NH 3 gas. Table 1 shows the comparison between the present work and previously reports on gas sensing properties for NH 3 detection [51][52][53][54][55][56]. Compared with other gas sensing materials, the rGO/Cu 2 O nanocomposites exhibit high response and rapid response/recovery rate [52,57].…”