Table 1.
FTIR peaks and functional groups present on precousor and synthesized carbon dots.
| Sr. No | Name of Compound | Functional Group | Frequency |
|---|---|---|---|
| 1. | Citric Acid | A. O–H stretching vibration | 3283 & 3493 |
| B. C O stretching vibration | 1741 | ||
| C. C–OH stretching vibration | 1138 | ||
| D. CH2 rocking | 769 | ||
| 2. | PBA | A. O–H stretching vibration | 3139 |
| B. B–O stretching vibration | 1322 | ||
| C. C O stretching vibration | 1677 | ||
| D. CH2 bending vibration | 1262, 1188 | ||
| 3. | Raw Chitosan | A. O–H & N–H stretching vibration | 3327 |
| B. C–H stretching vibration | 2875 | ||
| C. NH2 bending vibration | 1648 & 1568 | ||
| D. C C, C N and C C–O stretching | 1375–1148 | ||
| E. CH2 bending vibrations | 1024–900 | ||
| 4. | Raw PEI 2kd | A. N–H stretching vibration | 3300 |
| B. C–H stretching vibration | 2842 & 2946 | ||
| C. NH2 bending vibration | 1603 | ||
| D. CH2 bending vibration | 1464 | ||
| E. C–N stretching vibration | 1107 | ||
| 5. | Raw PEI 25 kd | A. N–H stretching vibration | 3294 |
| B. C–H stretching vibration | 2811 & 2935 | ||
| C. NH2 bending vibration | 1594 | ||
| D. CH2 bending vibration | 1454 | ||
| E. C–N stretching vibration | 1107 | ||
| 6. | CS-CDs | A. O–H and N–H stretching vibration | 3378 |
| B. C O stretching vibration | 1727 | ||
| C. C C stretching vibration | 1638, 1071 | ||
| D. NH2 bending vibration | 1506 | ||
| E. C–O stretching vibration | 1071 | ||
| F. CH2 bending vibration | 1014 | ||
| 7. | PEI2-CDs | A. O–H and N–H stretching vibration | 3335 |
| B. C–H stretching vibration | 2921 | ||
| C. C O stretching vibration | 1700 | ||
| D. C C stretching vibration | 1642 | ||
| E. CH2 bending vibration | 1430 | ||
| F. C–O stretching vibration | 1071 | ||
| 8. | PEI25-CDs | A. O–H and N–H stretching vibration | 3348 |
| B. C–H stretching vibration | 2969 | ||
| C. C O stretching vibration | 1705 | ||
| D. C C stretching vibration | 1637 | ||
| E. CH2 bending vibration | 1456 | ||
| F. C–O stretching vibration | 1055 | ||
| 9 | CP2-CDs | A. O–H and N–H stretching vibration | 3348 |
| B. C–H stretching vibration | 2969 | ||
| C. C O stretching vibration | 1714 | ||
| D. C C stretching vibration | 1617, 1064 | ||
| E. NH2 bending vibration | 1507 | ||
| F. C–N stretching vibration | 1194 | ||
| G. C–O stretching vibration | 1064 | ||
| 10. | CP25-CDs | A. O–H and N–H stretching vibration | 3365 |
| B. C–H stretching vibration | 2929 | ||
| C. C O stretching vibration | 1727 | ||
| D. C C stretching vibration | 1617, 1067 | ||
| E. NH2 bending vibration | 1511 | ||
| F. C–N stretching vibration | 1182 | ||
| G. C–O stretching vibration | 1067 |