Table 2.
Recent advances in the preparation of CDs, their corresponding properties, and Fe3+ ion sensing performance
| Precursors | Synthesis route | QY (%) | Linear range | LOD | References |
|---|---|---|---|---|---|
| Chemical precursor | |||||
| Citric acid and guanidinium | Solid-phase pyrolysis | 19.2 | 0–200 µM | 100 nM | [114] |
| 2,5-diaminobenzenesulfonic acid and 4-aminophenylboronic acid hydrochloride | Hydrothermal | 5.44 | 0.3–546 µM | 90 nM | [115] |
| Folic acid, 3-aminopropyl trimethoxy silane, glycerol | Hydrothermal | 46 | 10 nM–45 µM | 3.8 nM | [116] |
| Citric acid, diammonium hydrogen phosphate | Hydrothermal | 59 | 20–200 µM | 20 µM | [117] |
| Adenosine 5′triphosphate | Hydrothermal | 43.2 | 1–150 µM | 0.33 µM | [112] |
| l-glutamic acid | Solid-phase microwave-assisted pyrolysis | 41.2 | – | 10−5 M | [118] |
| dl-malic acid, ethanolamine, ethane-sulfonic acid | Microwave-assisted pyrolysis | 15.13 | 6–200 µM | 0.8 µM | [119] |
| Chitosan, acetic acid and 1,2-ethylenediamine | Microwave-assisted pyrolysis | 20.10 | 0.01–1.8 ppm | 10 ppb | [111] |
| Anhydrous citric acid, 1–10 phenanthroline | Pyrolysis | 10 | 0–50 µM | 35 nM | [120] |
| Aminosalicylic acid | Solvothermal | 16.4 | 1–250 µM | 0.52 µM | [121] |
| Green precursors | |||||
| Mangosteen pulp | Pyrolysis | – | 0–0.18 mM | 52 nM | [122] |
| Coffee ground | Hydrothermal | 5 | – | 9 nM | [123] |
| Jujubes | Hydrothermal | – | 0–200 µM | – | [124] |
| Sweet potatoes | Hydrothermal | 8.64 | 1–100 µM | 0.32 µM | [125] |
| Jinhua bergamot | Hydrothermal | 50.78 | 0.025–100 µM | 0.075 µM | [38] |
| Rose-heard radish | Hydrothermal | 13.6 | 0.02–40 µM | 0.13 µM | [113] |