Blue Organic Long Persistent Luminescence: A UV/Violet‐Light‐Excitable and Green/Red‐Light‐Erasable Donor‐Sensitizer‐Acceptor Organic Afterglow System

< 450 nm; such pure-blue OLPL materials remain elusive in the reported studies. Mechanistic investigations confirm a unique charge-separation-induced OLPL pathway, involving electron transfer processes between donor, sensitizer, and acceptor. The OLPL materials are UV/visible-light-excitable. Remarkably, it is found that the OLPL emission can be erased by green or red light; the long-lived excited TADF sensitizers can be pushed by green/red lights to higher excited states, followed by fast nonradiative deactivation, enabling optical erasure. This unprecedented optical write-erase functionality, coupled with hour-long OLPL duration, would offer promising opportunities for rewritable photonic storage, encryption, and dynamic labeling applications.