Synchronizing Excited-State Lifetimes for Bright and Long-Lived White Phosphorescent Carbon Nanodots.

Li, Xiang-Yu; Liu, Si-Tao; Cao, Qing; Song, Shi-Yu; Gao, Meng-Di; Gao, Chao-Jun; Zhang, Wen-Shuo; Zhao, Wen-Bo et al. · Nano Lett · 2025

basic_science · Level V

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Abstract

White phosphorescent materials are highly desirable for delayed lighting and advanced display applications; however, their development is hindered by time-dependent spectral changes and low efficiency. Herein, we report bright and long-lived white phosphorescence from carbon nanodots (CNDs) achieved by synchronizing excited-state lifetime engineering yielding white phosphorescent CNDs with a lifetime of 800 ms and a quantum efficiency of 27.9%. A secondary carbonization strategy synchronizes multiple emission centers, enabling stable white phosphorescence over 6 s, tunable correlated color temperature (4400-7990 K), and CIE coordinates (0.29, 0.32) to (0.36, 0.34). Moreover, integration of these CNDs into a light emitting diode (LED) demonstrates delayed white emission with suppressed flicker under alternating-current excitation, providing eye-friendly illumination. Programmable delayed LED arrays reconstruct temporally fragmented signals into coherent images. This work demonstrates a robust strategy for bright and long-lasting white phosphorescent materials, laying the foundation for advanced delayed lighting and programmable display applications.