Photoactivatable Time‐Evolving Afterglow of Carbon Dots via Coupled Triplet and Exciplex Persistent Emission for Programmable Photonic Encoding

Photoactivatable time-evolving afterglow color (TEAC) materials offer programmable delayed emission for dynamic photonic applications. However, achieving light-triggered and multistate afterglow control in metal-free systems remains a formidable challenge. Here we report a carbon dot-polymer composite (CDs@ABS) that exhibits dual photoactivatable delayed emissions with distinct lifetimes, generating reversible TEAC with optical memory. Upon brief UV exposure, the film shows no visible afterglow; prolonged irradiation activates a dynamic emission that evolves from red to orange, yellow, and finally green, with a memory duration of up to 40 min and excellent long-term stability. In this architecture,…

• NN
  National Natural Science Foundation of China

  Awards: 22305052, 22205122, 22302012
• NS
  Natural Science Foundation of Beijing Municipality

  Award: 2252037
• NS
  Natural Science Foundation of Shandong Province

  Awards: ZR2024MB089, ZR2020QE052
• NK
  National Key Research and Development Program of China
• FR
  Fundamental Research Funds for the Central Universities

  Award: 2253200006