Hydrogen Bonding-Induced Oxygen Clusters and Long-Lived Room Temperature Phosphorescence from Amorphous Polylols

The study of non-conjugated luminescent polymers (NCLPs) with fluorescence and long-lived room-temperature phosphorescence is of great significance for revealing the essence of NCLPs luminescence, which has gradually attracted the attention of researchers in recent years. Herein, polymethylol (PMO) and poly(3-butene-1,2-diol) (PBD) with polyhydroxyl structures were prepared and their luminescence behaviors were investigated to further reveal the clusteroluminescence (CL) mechanism. Compared with the weak or even non-luminescent behavior of polyvinyl alcohol, PMO and PBD exhibit cyan-blue fluorescence with quantum yields of ca. 12% and green room-temperature phosphorescence with lifetimes of ca. 89 ms in the solid state. Both fluorescence and phosphorescence exhibit typical excitation-dependent CL behavior. Experimental and theoretical analyses show that the strong hydrogen-bonding interaction of PMO and PBD greatly promotes the formation of oxygen clusters and the through-space n-n interaction of oxygen atoms, enabling fluorescence and phosphorescence emission. The results of this work have important implications for understanding the clusteroluminescence mechanism of NCLPs and provide a new polymer design strategy for the rational design of novel NCLPs materials.