A Facile Strategy for Achieving Polymeric Afterglow Materials with Wide Color‐Tunability and Persistent Near‐Infrared Luminescence

Abstract

Polymer‐based room‐temperature phosphorescence (RTP) materials show promising applications in anti‐counterfeiting. To further realize multiscale and/or multimodal anti‐counterfeiting, it is highly desirable to develop polymeric afterglow materials with multiple security features. Herein, a facile strategy is presented to endow polymeric afterglow materials with ultralong lifetime, wide color‐tunability, persistent near‐infrared (NIR) luminescence, and good water solubility via constructing non‐traditional phosphorescence resonance energy transfer (PRET) and two‐step sequential resonance energy transfer systems. Specifically, the 1‐bromocarbazole derivatives with ultralong blue‐color RTP property act as the energy donor while traditional dyes with red/NIR luminescence act as the energy acceptor. By simply regulating the doping composition and concentration of these non‐traditional energy transfer systems, persistent and multicolor organic afterglow covering from the visible to NIR region is successfully realized. Notably, compared to the single‐step PRET, the two‐step sequential resonance energy transfer has the unique advantages of higher transfer efficiency of triplet excitons from the initial donor, a wider range of color‐tunability mediated by the intermediary acceptor, and enhanced delayed fluorescence efficiency of the final acceptor. Finally, these water‐soluble polymeric afterglow materials with ultralong lifetime, wide color‐tunability, and persistent NIR luminescence show great potential applications in advanced anti‐counterfeiting and information security technologies.

Advances in Polymer‐Based Organic Room‐Temperature Phosphorescence Materials

“…Immediately, excitons in the S 1 state of RB transferred their energy to the target Cy7, thus resulting in NIR persistent luminescence (Figure 17). Such emission properties and mechanisms were further demonstrated by Xiong and co-workers [91] from (1-bromo-9H-carbazol-9-yl)(4-methoxyphenyl)methanone-doped PVA (28 in Scheme 9) in 2023. Afterglow color was successfully modulated from the visible to the NIR region by adjusting the doping composition and concentration to control the energy transfer process.…”

Simultaneously enhancing organic phosphorescence quantum yields and lifetimes for triphenylphosphine salt doped polymer films

“…25–29 Particularly, polyvinyl alcohol (PVA) emerges as a promising host matrix due to its water solubility and flexibility, which promote low-cost and eco-friendly processing. 25–27,30–33 However, a challenge arises as most guest molecules are oil-soluble and tend to undergo phase separation at high doping concentrations in the PVA matrix. 30–33 Therefore, developing hydrophilic guest molecules that can integrate effectively into a PVA matrix with persistent RTP properties is of crucial importance.…”

“…25–27,30–33 However, a challenge arises as most guest molecules are oil-soluble and tend to undergo phase separation at high doping concentrations in the PVA matrix. 30–33 Therefore, developing hydrophilic guest molecules that can integrate effectively into a PVA matrix with persistent RTP properties is of crucial importance.…”

Enhanced X-ray Imaging with Gd2O2S:Pr-Epoxy Composite Films: Synthesis, High-Resolution Performance, and Flexibility

“…Scintillation materials, which emit light when excited by high-energy particles, are available in various forms, including organic, − inorganic, − and organic–inorganic composite scintillators. , Organic scintillators offer quick response and flexibility but suffer from lower efficiency and radiation resistance. − In contrast, inorganic scintillators deliver higher efficiency and durability but at a higher cost and with fabrication limitations. − Organic–inorganic composite scintillators, combining organic substances with inorganic scintillation components, offer a promising solution by merging the benefits of both types, such as cost-effectiveness and tunable scintillation properties . These advantages of organic–inorganic composite scintillators make them suitable for practical applications in X-ray panel imaging.…”