Multicolor Ultralong Organic Phosphorescence through Alkyl Engineering for 4D Coding Applications

Luminogens with colorful ultralong organic phosphorescence (UOP) are in high demand because of various potential applications in optoelectronics. Herein, we report a concise approach to tune UOP based on the same chromophores of carbazole and phthalimide units through alkyl engineering. With flexible alkyl increase, UOP emission colors can be controllably tuned from green to orange along with lifetime variation. Furthermore, these phosphors were endowed with unexpected visible-light excitation, mechanochromism, and mechanoluminescence properties simultaneously. Additionally, colorful UOP with diverse emission lifetime was first applied to the 4D code for information encryption. These findings will open a door to explore multifunctional organic phosphorescence materials and expand their potential applications.