江南大学林恒伟团队报道了通过能量间隙调节实现碳点基激合体系的秒到小时可调有机长持续发光。相关研究成果发表在2024年3月13日出版的《中国化学》。

持续时间可调的余辉材料在各种应用中引起了相当大的关注。

该文首次设计并制备了基于碳点（CDs）的持久发光（LPL）复合材料，该复合材料具有在秒到小时的超宽范围内可调的持续时间。与已建立的基于CD的余辉材料相比，研究人员报道了基于CD的复合材料以激发光复合物和长寿命电荷分离态的形式表现出LPL，使LPL从几秒钟延长到一个多小时，超过了典型的调节范围（限制在1分钟内）。

进一步的研究表明，CDs的激发态和电荷转移态之间的关系在激活LPL和调节其持续时间方面起着关键作用。此外，这些复合材料表现出高达60.63%的高光致发光（PL）量子产率，并且它们的LPL在环境条件下，甚至在水性介质中也是稳健的。它们强大而卓越的LPL性能使这些复合材料在动态显示系统中具有强大的竞争优势，例如用于时间分辨数据加密的标签和外卖剩余时间的显示。

该项研究为制备具有可调持续时间的CDs基LPL复合材料提供了一种方法，并可能为开发无稀土LPL材料提供新的见解。

附：英文原文

Title: Achieving Seconds-to-Hours Duration-Tunable Organic Long Persistent Luminescence from Carbon Dots-Based Exciplex Systems by Energy Gaps Regulation†

Author: Yixuan Xu, Kai Jiang, Linger Feng, Xinyuan Tong, Zuxu Zhou, Fengshi Li, Yi Zhang, Jiaren Du, Hengwei Lin

Issue&Volume: 2024-03-13

Abstract: Duration-tunable afterglow materials have garnered considerable attention in various applications. Herein, carbon dots (CDs)-based long persistent luminescence (LPL) composites with a tunable duration in an ultrawide range of seconds-to-hours levels were designed and prepared for the first time. In contrast to the established CD-based afterglow materials, we reported that CD-based composites exhibit LPL in the form of exciplexes and long-lived charge-separated states, enabling the LPL to be prolonged from several seconds to over one hour, exceeding the typical regulation range (limited to 1 min). Further studies revealed that the relationship between the excited and charge-transfer states of CDs plays a pivotal role in activating the LPL and regulating its duration. Furthermore, these composites exhibited high photoluminescence (PL) quantum yields of up to 60.63%, and their LPL was robust under ambient conditions, even in aqueous media. Their robust and superior LPL performance endows these composites with a strong competitive advantage in dynamic display systems, such as tags for time-resolved data encryption and displays of the remaining time of takeaways. This study offers an approach to preparing CDs-based LPL composites with tunable durations and may provide new insights for the development of rare-earth-free LPL materials.

DOI: 10.1002/cjoc.202300795

Source: https://onlinelibrary.wiley.com/doi/full/10.1002/cjoc.202300795