Carbonized polymer dots-based room temperature phosphorescence composites for anti-counterfeiting and white light-emitting diodes

Carbonized polymer dots (CPDs) have been studied extensively for room temperature phosphorescence (RTP) due to their low cost, good biocompatibility and crosslink-enhanced emission effect. Although considerable achievements have been reached in recent years, it is still a formidable task to prepare long-lived RTP CPDs. Herein, the Arg-CPDs was introduced into a rigid boric acid (BA) matrix to enhance the RTP lifetime of the Arg-CPDs@BA composites. The nitrogen-rich arginine framework integrated with phosphorus doping enhances spin-orbit coupling and accelerates the intersystem crossing and promotes the generation of triplet excitons. The formed C B covalent bond between Arg-CPDs and rigid B 2 O 3 matrix restricts the vibration and rotation of CPDs, thus inhibiting the non-radiative transition of the triplet excitons and making the composite exhibit a relatively long-lived RTP emission of 983 ms (18 s for naked eyes). It was nearly seven times longer than that of the matrix-free Arg-CPDs. Besides, the potential applications in anti-counterfeiting and white light-emitting diodes were demonstrated.