Handbook of Aggregation-Induced Emission, Volume 3

Pucci et al. shifted their attention to the compatibility issues that adversely affected the performances of LSC based on the TPE‐AC AIEgen. Notably, red‐emitting PMMA polymers (PMMA_TPE_RED) prepared via ATRP, already reported by the same authors as vapochromic plastic films, were effectively utilized as solar collectors ( Figure 3.12) [113].

Figure 3.12 Chemical structure of the PMMA_TPE_RED and photo of the derived LSC obtained by casting a solution of the polymer over a glass slab of G = 16.6 under the illumination with a solar simulator.

ATRP was actually exploited to obtain the desired polymeric AIEgen architecture aimed at providing phase stability between the fluorophore and the polymer matrix, which is an essential characteristic for high‐performance LSC. Notably, red‐emitting PMMA_TPE_RED films showed a Φ Fof 26.5%, and in dispersion with 50 wt.% of PMMA, it provided 30‐μm thick blend films with max optical efficiencies of 10%. This result was reported the highest ever registered with the same G factor (16.6) and therefore consistent for the AIEgen utilization in LSC technology.

Since the discovery of the first AIEgen, enormous and conspicuous advancements have been made in many sectors and field of science. In the closing remarks of the Faraday discussion on AIE held in Guangzhou, China, in November 2016, Bin Liu properly described the history of the AIE phenomenon from its discovery and mechanistic studies to real‐life applications in optoelectronics, environmental monitoring, and biomedical research [114]. This inspiring talk illuminated several authors in providing AIEgens with even more intriguing characteristics and applications. In this regard, this contribution aimed to convince the readership about the potential offered by the AIE technology in producing fluorescent plastic films that are able to provide optical outputs to be used in sensing applications or in the energy field for solar harvesting. The AIEgens prove to be the best candidates to dope polymer films due to their high brilliant and high emission in the solid state that can be easily perturbed by external solicitations such as a mechanical, thermal, or chemical stress. OFF–ON fluorescence outputs were demonstrated to be more appealing than the corresponding ON–OFF ones since easily detectable responses with high contrast can be gathered. The AIE technology not only paved the way for practical sensing applications but also enabled the design and realization of highly luminescent polymer films in solar harvesting. LSCs appear as one of the most promising solutions to increase the diffusion of the PVs in the urban environment. A high Φ Fand a well‐compatible AIEgen with low autoabsorption losses were demonstrated to be the perfect candidates to dope plastic films and slabs to maximize sunlight collection and increase the optical efficiency. In conclusion, the versatile chemistry of AIEgens will enable the preparation of even more efficient fluorophores that will be helpful in many fields of science, comprising polymeric materials.

This work would not have existed without the fundamental support of Dr. Giuseppe Iasilli and Dr. Pierpaolo Minei, who contributed to the success of the Smart Polymer Group in Pisa. The financial support by the MIUR‐PRIN 20179BJNA2 is kindly acknowledged.

1 1 de Silva AP, Gunaratne HQN, Gunnlaugsson T, Huxley AJM, McCoy CP, Rademacher JT, et al. (1997). Signaling recognition events with fluorescent sensors and switches. Chem. Rev. 97(5): 1515–66.

2 2 McQuade DT, Pullen AE, Swager TM (2000). Conjugated polymer‐based chemical sensors. Chem. Rev. 100(7): 2537–74.

3 3 Adhikari B, Majumdar S (2004). Polymers in sensor applications. Progr. Polym. Sci. 29(7): 699–766.

4 4 Thomas SW, III, Joly GD, Swager TM (2007). Chemical sensors based on amplifying fluorescent conjugated polymers. Chem. Rev. 107(4): 1339–86.

5 5 Winnik FM, Whitten DG, Urban MW, Lopez G (2007). Stimuli‐responsive materials: polymers, colloids, and multicomponent systems. Langmuir 23(1): 1–2.

6 6 Wu J, Liu W, Ge J, Zhang H, Wang P (2011). New sensing mechanisms for design of fluorescent chemosensors emerging in recent years. Chem. Soc. Rev. 40(7): 3483–95.

7 7 Schaeferling M (2012). The art of fluorescence imaging with chemical sensors. Angew. Chem. Int. Ed. 51(15): 3532–54.

8 8 Lodeiro C, Capelo JL, Mejuto JC, Oliveira E, Santos HM, Pedras B, et al. (2010). Light and colour as analytical detection tools: a journey into the periodic table using polyamines to bio‐inspired systems as chemosensors. Chem. Soc. Rev. 39(8): 2948–76.

9 9 Basabe‐Desmonts L, Reinhoudt DN, Crego‐Calama M (2007). Design of fluorescent materials for chemical sensing. Chem. Soc. Rev. 36(6): 993–1017.

10 10 Demchenko AP (2009). Introduction to Fluorescence Sensing. Springer: Netherlands.

11 11 Valeur B, Berberan‐Santos MN (2012). Molecular Fluorescence: Principles and Applications. Weinheim (Germany): Wiley‐VCH.

12 12 Nadler A, Schultz C (2013). The power of fluorogenic probes. Angew. Chem. Int. Ed. 52(9): 2408–10.

13 13 Pucci A, Bizzarri R, Ruggeri G (2011). Polymer composites with smart optical properties. Soft Mat. 7(8): 3689–700.

14 14 Pucci A, Ruggeri G (2011). Mechanochromic polymer blends. J. Mater. Chem. 21(23): 8282–91.

15 15 Urban MW (2011). Handbook of Stimuli‐Responsive Materials. Weinheim, Germany: Wiley‐VCH Verlag GmbH & Co. KGaA.

16 16 Ciardelli F, Ruggeri G, Pucci A (2013). Dye‐containing polymers: methods for preparation of mechanochromic materials. Chem. Soc. Rev. 42(3): 857–70.

17 17 May PA, Moore JS (2013). Polymer mechanochemistry: techniques to generate molecular force via elongational flows. Chem. Soc. Rev. 42(18): 7497–506.

18 18 Luo J, Xie Z, Lam JWY, Cheng L, Chen H, Qiu C, et al. (2001). Aggregation‐induced emission of 1‐methyl‐1,2,3,4,5‐pentaphenylsilole. Chem. Commun. (Camb. UK) (18): 1740–1.

19 19 Hong Y, Lam Jacky WY, Tang BZ (2011). Aggregation‐induced emission. Chem. Soc. Rev. 40(11): 5361–88.

20 20 Hong Y, Lam JWY, Tang BZ (2009). Aggregation‐induced emission: phenomenon, mechanism and applications. Chem. Commun. (Camb. UK) (29): 4332–53.

21 21 Hong Y, Lam Jacky WY, Tang Ben Z (2011). Aggregation‐induced emission. Chem. Soc. Rev. 40(11): 5361–88.

22 22 Mei J, Hong Y, Lam JWY, Qin A, Tang Y, Tang BZ (2014). Aggregation‐induced emission: the whole is more brilliant than the parts. Adv. Mater. (Weinheim, Ger.) 26(31): 5429–79.

23 23 Qiu Z, Liu X, Lam JWY, Tang BZ (2019). The marriage of aggregation‐induced emission with polymer science. Macromol. Rapid Commun. 40(1): 1800568.

24 24 Hu R, Kang Y, Tang BZ (2016). Recent advances in AIE polymers. Polym. J. (Tokyo, Jpn.) 48(4): 359–70.

25 25 Hu R, Lam JWY, Tang BZ. AIE‐active Polymers. John Wiley & Sons Ltd.; 2014. p. 253–83, 3 plates.

26 26 Hu R, Leung NLC, Tang BZ (2014). AIE macromolecules: syntheses, structures and functionalities. Chem. Soc. Rev. 43(13): 4494–562.

27 27 Hu YB, Lam JWY, Tang BZ (2019). Recent progress in AIE‐active polymers. Chin. J. Polym. Sci. 37(4): 289–301.

28 28 Qin A, Lam JWY, Tang BZ (2012). Luminogenic polymers with aggregation‐induced emission characteristics. Prog. Polym. Sci. 37(1): 182–209.

29 29 Pucci A, Ruggeri G, Bronco S, Bertoldo M, Cappelli C, Ciardelli F (2007). Conferring dichroic properties and optical responsiveness to polyolefins through organic chromophores and metal nanoparticles. Progr. Org. Coat. 58(2–3): 105–16.