Abstract: Carbonized polymer dots (CPDs), as an important branch of carbon dots (CDs), have demonstrated remarkable performance and processing and molding advantages in the field of solid-state luminescent materials due to their unique sub-fluorescent groups and polymer-like structures. Specifically, the sub-fluorescent groups in the shell of carbonized polymer dots avoid the generation of π-π interactions due to the presence of polymer components, thereby effectively alleviating the quenching (ACQ) caused by aggregation. Therefore, carbonized polymer dots are ideal and highly efficient solid-state luminescent materials with development potential. To achieve efficient solid-state luminescence of carbonized polymer points (CPDs), a series of CPDs were prepared in this paper using linear polyacrylic acid (PAA) and organic small molecules of different functionalities as co-precursors through a hydrothermal process. The polymer molecular chain on the outer layer of CPDs isolates and disperses the fluorescence center, effectively suppressing the aggregation-induced quenching (ACQ) effect and ensuring the solid-state luminescence performance. Based on the cross-linked enhanced emission (CEE) mechanism, the influence of the average functionality of co-precursors on the luminescence performance of CPDs was systematically studied. The experimental results show that with the increase of the functionality and crosslinking degree of the precursors, the fluorescence quantum yield and room-temperature phosphorescence (RTP) lifetime of CPDs are significantly enhanced, effectively improving the solid-state luminescence performance.

Key words: Carbonized polymer dots, Carbon dots, Solid-state luminescence, Crosslink-enhanced emission effect, Functionality of precursor