Enabling Highly Robust Full‐Color Ultralong Room‐Temperature Phosphorescence and Stable White Organic Afterglow from Polycyclic Aromatic Hydrocarbons

In this work, full-color and stable white organic afterglow materials with outstanding water, organic solvents, and temperature resistances have been developed for the first time by embedding the selected polycyclic aromatic hydrocarbons into melamine-formaldehyde polymer via solution polymerization. The afterglow quantum yields and lifetimes of the resulting polymer films were up to 22.7% and 4.83 s under ambient conditions, respectively. For the coronene-doped sample, its afterglow color was linearly tunable between yellow and blue by temperature, and it could still emit intense blue afterglow with a lifetime of 0.68 s at 440 K. Moreover, the films showed bright and stable white afterglow at 370 K with a lifetime of 2.80 s and maintained excellent afterglow performance after soaking in water and organic solvents for more than 150 days. In addition, the application potential of the polymer films in information encryption and anti-counterfeiting was also demonstrated.