Table 5.
Summary of optical properties and sensing performance of AIE-based cyanide chemosensors B1a–B14.
| λabs (nm) a |
λem (nm) b |
Φ (%) c |
Original Emission Colour | Emission Colour/Change in the Presence of Anion | L.O.D d | Mechanism of Detection | Ref. | |
|---|---|---|---|---|---|---|---|---|
| B1a | ~400 (aggr) f | 547 (aggr) f | - | Green-yellow (aggr) f | Weak blue | 63 ppm | Nucleophilic addition of CN− to dicyanovinyl- group | [73] |
| B1b | ~400 (aggr) f | 565 (aggr) f | - | Orange (aggr) f | Weak blue | 109 ppm | Nucleophilic addition of CN− to dicyanovinyl- group | [73] |
| B2a | 387–407 (soln) e | 628 (soln) e; 600 (aggr) f | 24 (Solid) g | Orange (aggr) f | Quenched | 0.32 μM | Nucleophilic addition of CN− to dicyanovinyl- group | [74] |
| B2b | 385–404 (soln) e | 625 (soln) e; 600 (aggr) f | 22 (Solid) g | Red (soln) e; orange (aggr) f | Quenched | 0.29 μM | Nucleophilic addition of CN− to dicyanovinyl- group | [74] |
| B3a | 437 (soln) e; 465 (aggr) f | 568 (aggr) f | - | Orange (aggr) f | Quenched | 9.88 nM | Nucleophilic addition of CN− to dicyanovinyl- group | [75] |
| B3b | 440 | 650 (aggr) f | - | Red (aggr) f | Quenched | 0.11 nM | Nucleophilic addition of CN− to dicyanovinyl- group | [76] |
| B4 | 340, 390, 460 (soln) e | 605 (soln) e | - | Orange (soln) e | Quenched | - | Nucleophilic addition of CN− to dicyanovinyl- group | [77] |
| B5 | ~450 (aggr) f | 580 (aggr) f | - | Orange (aggr) f | Quenched | 0.22 μM | Nucleophilic addition of CN− to cyanoethylene- group | [78] |
| B6a | 562 (soln) e | - | - | Non emissive (aggr; solid) f,g | Blue | 24.5 μM | Nucleophilic addition of CN− to 1,1-dicyanomethylidene group | [79] |
| B6b | 443 (soln) e | 629 (aggr) f; 653 (solid) g | - | Weak red (aggr, solid) f,g | - | 1.7 μM | Nucleophilic addition of CN− to 1,1-dicyanomethylidene group | [79] |
| B6c | 386 (soln) e | 573 (soln) e; 543 (solid) g | 0.4 (soln) e; 3.0 (aggr) f | Yellow (aggr; solid) f,g | Blue | 5.07 μM | Nucleophilic addition of CN− to 1,1-dicyanomethylidene group | [79] |
| B7 | 380 | 435 | - | Blue | Enhanced | 55 nM | Nucleophilic attack of CN− to indolium moiety disrupts ICT effect | [80] |
| B8 | 434 (soln) e | 547 (soln) e; 623 (aggr) f | - | Green (soln) e; orange (aggr) f | Quenched | 67.4 nM | Nucleophilic attack of CN− to C=C bond interrupting ICT between carbazole and barbituric acid | [81] |
| B9 | 356 (soln) e | n.d. (soln; aggr) e,f; 464 (soln, +CN−) e,h; 508 (aggr, +CN−) f,h | 36.6 (soln, +CN−) e,h | No emission | Blue (soln) e green (aggr) f |
0.592 μM | Underwent oxidative cyclization reaction after deprotonation of −OH by CN− to generate hydroxyphenyl-benzoxazole | [82] |
| B10 | 396, 411 (soln) e | 530 (soln) e; 584 (aggr) f | 0.21 (solid) g | Green (aggr) f | Yellow | 0.81 μM | Deprotonation of OH groups by CN− leading to ICT effect that red-shifts fluorescence | [83] |
| B11 | 410 (soln) e | 516 (Gel); 498 (Gel, +CN−) g,h |
- | Green (gel) g | Blue (gel) g | 3.02 μM | Deprotonation of OH and NH groups by CN− disrupts hydrogen bonding in self-assembly | [84] |
| B12 | - | 410 (aggr) f | 11.24 (soln) e; 37.8 (aggr) f | Blue (aggr) f; quenched (+Hg2+) h | Blue FL recovered | 77.1 nM | CN− reinstates self-assembly of B12 by removing Hg2+ in B12-Hg adduct as Hg(CN)2 | [85] |
| B13 | ~345 | 435 (aggr) f | - | Blue (aggr) f; quenched (+picric acid) h | Blue FL recovered | 0.745 μM | CN− reinstates self-assembly of B13 by causing B13-Picric acid adduct to break apart | [86] |
| B14 | 313 | 498 (soln) e; 458 (aggr) f | 3.9 (soln) e; 24 (aggr) f | - | Blue, turn-on | 0.59 μM | Coordination of CN− to Co(II) centre decreases complex solubility | [87] |
a Absorption maxima; b Emission maxima; c Fluorescence quantum yield; d Limit of Detection; e (soln) denotes optical properties in solution state; f (aggr) denotes optical properties of aggregates; g (solid/film/gel) denotes optical properties in solid/film/gel state; h (+Xn+/−) denotes optical properties in the presence of ion Xn+/−. “-”: data were not reported.