The Simpler, the Better: Organic Materials with Adsorption‐Induced Room‐Temperature Phosphorescence for Anti‐Counterfeiting and Dyeing Applications

Abstract

In recent years, organic room‐temperature phosphorescence (RTP) has been widely investigated owing to its fascinating afterglow characteristics. Consequently, it has been applied in anti‐counterfeiting and information security. However, these applications are limited by cost, substrates, and technological processes. Hence, a simple and environmentally friendly adsorption‐induced RTP system containing sulfonic acid groups is designed for convenient and efficient application. A pure organic compound of (1,1″‐biphenyl)‐4,4″‐disulfonic acid can be easily ionized and dispersed in water. When it is adsorbed on different types of paper and cloth substrates rich in hydroxyl groups, bright RTP emissions with maximum lifetimes of ≈1.1 s are achieved after drying the substrates. The destructive effect of H2O on the intermolecular hydrogen bonds between the phosphor and substrates makes the RTP emissions responsive to the stimuli of water and heat. Furthermore, a white afterglow is realized after doping with Rhodamine B for energy transfer. On the account of the adsorption‐induced RTP effect, four economical applications are demonstrated, wherein one dollar's worth of the phosphor can be used for anti‐counterfeiting 7692 banknotes, printing and dyeing 1538 graphs on cloth, making 196 Chinese knots, and producing 385 writes of encryption information, promoting the further development and commercialization of RTP materials.

Functionalized tails influence photoluminescence emissions for advanced applications in the fiel of time-resolved information input and erasure

“…Additionally, Cz–C 8 was synthesized as a control molecule due to its lack of a functional tail while the introduction of a –Br group is potentially beneficial to improve the spin–orbital coupling (SOC) and promote ISC processes due to the heavy atom effect. 4,20,29,40 The other tails have more polar functional groups with a high capacity for the intermolecular interactions, such as hydrogen bonding 7,25,27 and dipole–dipole interactions. 19,49 These interactions are able to rigidify the motion of luminophores, further depressing the nonradiative decay of triplet excitons, and thus boosting the phosphorescence emission of luminophores.…”

“…However, from an organic chemistry point of view, the regulation of the chemical structure at a molecular level 4,20 is the cornerstone for all development in materials science. The most impressive works related to chemical structure regulation were documented from Li, 22–28 An, 29–34 Liu, 35–37 Chi, 38–41 and Ma et al groups, 42–47 whose findings absolutely made a major but outstanding contribution for the development of ORTP materials.…”

Water/Light Multiregulated Supramolecular Polypseudorotaxane Gel with Switchable Room-Temperature Phosphorescence

“…However, there are still some limitations in the regulation of the RTP emission. Therefore, tunable RTP materials responding to stimulus such as temperature, − humidity, − mechanical force, − pH, − and light − have attracted extensive attention, revealing their broad application prospects in chemical sensing, , information anticounterfeiting, , optoelectronic devices, , and biological imaging. , …”

Achieving time-dependent and color-tunable ultralong room temperature phosphorescence through sodiation reconfiguration for dynamic 5D information encryption

“…Room temperature phosphorescence (RTP) materials have recently received extensive attention because of their promising applications in anti-counterfeiting, 1–4 information encryption, 5,6 optical devices, 7,8 sensing, 9 and bioimaging. 10,11 From an application-oriented perspective, the construction of ultralong RTP materials with a lifetime exceeding 1 s is highly desired.…”