Table 2.
Functional groups associated with significant vibration bands in the mid-IR spectrum of P. sajor-caju, biosynthesized Ag NPs and Au NPs.
| S.N. | Wavenumber Range (cm−1) | Wavenumber (cm−1) P. sajor-caju |
Wavenumber (cm−1) Biosynthesized PS-Ag NPs | Wavenumber (cm−1) Biosynthesized PS-Au NPs |
Band Assignment and Functional Groups |
|---|---|---|---|---|---|
| 1. | 3029–3639 | 3379.3 | 3421.5 | 3418.3 | O-H stretching i.e., alcohol, phenolic compounds and groups N-H stretching (asymmetric) of Amide-A |
| 2. | 1583–1709 | 1650.2 | 1645.5 | 1674 | (C=C stretch) and stretch of amides C=O stretching of ester group |
| 3. | 1400–1000 | 1406.0 | 1420.1 | 1422.1 | A combination of hindered rotation and O-H bending |
| 4. | 1400–1000 | 1042.7 | 1021.7 | 1024.2 | C-N stretching |