Completely aqueous processable stimulus responsive organic room temperature phosphorescence materials with tunable afterglow color

Abstract

Many luminescent stimuli responsive materials are based on fluorescence emission, while stimuli-responsive room temperature phosphorescent materials are less explored. Here, we show a kind of stimulus-responsive room temperature phosphorescence materials by the covalent linkage of phosphorescent chromophore of arylboronic acid and polymer matrix of poly(vinylalcohol). Attributed to the rigid environment offered from hydrogen bond and B-O covalent bond between arylboronic acid and poly(vinylalcohol), the yielded polymer film exhibits ultralong room temperature phosphorescence with lifetime of 2.43 s and phosphorescence quantum yield of 7.51%. Interestingly, the RTP property of this film is sensitive to the water and heat stimuli, because water could destroy the hydrogen bonds between adjacent poly(vinylalcohol) polymers, then changing the rigidity of this system. Furthermore, by introducing another two fluorescent dyes to this system, the color of afterglow with stimulus response effect could be adjusted from blue to green to orange through triplet-to-singlet Förster-resonance energy-transfer. Finally, due to the water/heat-sensitive, multicolor and completely aqueous processable feature for these three afterglow hybrids, they are successfully applied in multifunctional ink for anti-counterfeit, screen printing and fingerprint record.

Manipulation of Triplet Excited States in Two‐Component Systems for High‐Performance Organic Afterglow Materials

“…Huang and coworkers found that the presence of water molecules can enhance hydrogen bonding between CA matrices and TMA dopants, leading to remarkable elongation of phosphorescence lifetimes [38] . On the contrary, in the case of PVA matrices and 1,1’:3’,1’’‐terphenyl‐5’‐boronic acid, Li and coworkers reported that the water and heat treatment can destroy hydrogen bonding between matrices and dopants, causing the decrease of afterglow performance [100] . Both of these two‐component systems can be used as stimuli‐responsive afterglow materials.…”

“…[38] On the contrary, in the case of PVA matrices and 1,1':3',1''-terphenyl-5'-boronic acid, Li and coworkers reported that the water and heat treatment can destroy hydrogen bonding between matrices and dopants, causing the decrease of afterglow performance. [100] Both of these two-component systems can be used as stimuli-responsive afterglow materials.…”

Cross‐linking enhanced room‐temperature phosphorescence of carbon dots

“…Room-temperature phosphorescence (RTP) is traditionally associated with inorganic materials (including some minerals), where their afterglow lifetimes can extend from minutes to hours following photoexcitation. [1][2][3] Although inorganic RTP materials with prolonged light emission are actively being sought for many applications including optoelectronic devices, photocatalysis, and emergency signage, [4][5][6][7] they are less suitable for applications such as anticounterfeiting and bioimaging materials, where bright, subsecond afterglow is required. [8][9][10] In general, RTP is difficult to achieve at room temperature due to the spin prohibition of triplet exciton transitions and the fact that triplet excitons are easily quenched by oxygen and other nonradiative processes.…”

Ultralarge Stokes Shift Phosphorescence Artificial Harvesting Supramolecular System with Near‐Infrared Emission

“…[ 10 ] However, such materials are hard to acquire because of the limitation by the energy gap law. [ 11 ] Recently, phosphorescence resonance energy transfer (PRET) has emerged as an alternative which can endow suitable fluorescent organic dyes with long lifetime via a delayed sensitization process, [ 12 ] showing greatly potential applications in time‐resolved bioimaging, [ 13 ] multicolor afterglow materials, [ 14 ] information encryption, and anticounterfeiting. [ 15 ] For example, George and coworkers have reported an organic–inorganic scaffolding strategy which can be used as a light‐harvesting platform to achieve delayed fluorescence via PRET process.…”