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

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.