Time-Dependent Dynamic Afterglow of Carbon Dots-Based Materials: Synthesis, Luminescence Mechanism, and Application

Time-dependent dynamic afterglow carbon dots (TDDA-CDs) demonstrate considerable application potential in the fields of anti-counterfeiting, information encryption, and light-emitting diodes (LEDs), owing to their excellent optical properties, low toxicity, and favorable biocompatibility. In recent years, many reports have been published on the TDDA phenomenon of CDs, and significant progress has been made. However, systematic summaries of CDs with TDDA are rare. This review provides a comprehensive summary of recent developments in TDDA-CDs, with particular emphasis on synthetic strategies, including matrix-assisted synthesis and matrix-free direct synthesis from raw materials. Furthermore, various proposed emission mechanisms are discussed in detail, such as dual room-temperature phosphorescence (RTP) centers, hybrid RTP/thermally activated delayed fluorescence (TADF) systems, and phosphorescence Förster resonance energy transfer (FRET)-mediated delayed fluorescence (DF) processes. Finally, the practical applicability of TDDA-CDs in anti-counterfeiting, information encryption, and LEDs is critically evaluated. This review aims to guide the rational design and development of multifunctional TDDA-CDs for advanced applications in secure information systems and intelligent optoelectronic devices.