Carbonized polymer dots-based composites with solution and solid-state room temperature phosphorescence for white light-emitting diodes

Although carbonized polymer dots (CPDs) have witnessed significant developments in the field room temperature phosphorescence (RTP) materials, how to improve the RTP lifetime remains a challenge. Herein, Arginine (Arg) and phosphoric acid were used to synthesize Arg-CPDs and then it was introduced into the SiO2 network where the C–Si bonds were created between the two components. The RTP emission of over 10 s can be found both in the Arg-CPDs@SiO2 solution and anhydrous Arg-CPDs@SiO2 composites. The anhydrous composites displayed an RTP lifetime of 543 ms, which was more than 3 times higher than that (149 ms) of the matrix-free Arg-CPDs materials. It is the result of the rigid SiO2 network inhibiting the vibration of light-emitting groups of Arg-CPDs and isolating them for preventing the quenching of triplet excitons. Besides, the Arg-CPDs@SiO2 composite was successfully applied to prepare white light-emitting diodes (WLEDs) and suggested the promising potential in the WLED illumination application.