Red Room Temperature Phosphorescence in Non-Aromatic Carbonized Polymer Dots

Achieving red organic room temperature phosphorescence (RTP) remains a significant challenge, especially in a non-aromatic system. Herein, red RTP with emission at 605 and 645 nm is achieved through inducing and confining carboxyl dimer association (CDA), a unique hydrogen-bonded coupling red phosphorescence unit, in non-aromatic carbonized polymer dots (CPDs). The CPDs are synthesized via microwave method by using polyacrylic acid (PAA), succinic acid (SA), and traces of phosphoric acid as precursors. Small molecule SA can flexibly enter the polymer cluster of PAA and pair with the isolated carboxyl groups to form CDA. The intrinsic local carbonized structure formed in CPDs can effectively stabilize CDA to achieve red RTP. The red afterglow can last for 1 s to naked eye, and the corresponding lifetimes for emission at 605 and 645 nm were 61 and 45 ms, respectively, after 365 nm excitation off. This work not only reported the non-aromatic red organic RTP materials for the first time, but also explored CPDs as an effective platform for achieving such non-aromatic long-wavelength RTP.