Table 4.
Overview of different nanomaterials used as active layers for detection of ammonia at room temperature.
| Polymer Type | LOD | Response Time/Recovery Time | Transducing Mechanism | Ref. |
|---|---|---|---|---|
| Nanofibrous PANI films | 5 ppm | ~200 s/~100 s | Chemiresistive | [122] |
| PbS quantum dots/TiO2 nanotube | 2 ppm | -/- | Chemiresistive | [121] |
| Co3O4 nanosheets | 0.2 ppm | ~9 s/~134 s | Chemiresistive | [121] |
| Carbon nanotubes/SnO2 nanocomposite | 10 ppm | ~100 s/~192 s | Chemiresistive | [123] |
| CuO Nanostructures | 50 ppm | ~6 min/~5–6 min | Chemiresistive | [120] |
| Au-decorated tungsten oxide nanoneedles | - | ~4 s/~4 min for 100 ppm | Optical | [124] |