Spatially Confined Single‐Phosphor Multichromatic Afterglow Based on Cyclodextrin Self‐Assembly

Abstract There is extensive research interest in sustainable, high‐performance persistent luminescent materials, featuring tunable organic afterglow and stimulus responsiveness, owing to their broad application potential. However, despite significant efforts by the scientific community, the value of single‐phosphor systems in achieving efficient persistent luminescence through multiple responses is not widely recognized. This work constructs a supramolecular self‐assembled system featuring multicolor phosphorescence, fabricated by incorporating (4‐(pyridin‐4‐yl)phenyl)boronic acid (PB3) into a biomass‐derived, macrocyclic β‐cyclodextrin (β‐CD) via multiple intermolecular interactions. Notably, the resulting PB3@β‐CD assembly exhibits both excitation‐dependent and visible‐light excitation capabilities, with an excitation wavelength range spanning 240–420 nm. When excited by white light, the afterglow persists for up to 3 s. Furthermore, the coexistence of isolated and aggregated states of PB3 within the β‐CD matrix causes the guest molecules to emit diverse afterglow colors under different excitation conditions. Compared to other matrices, PB3 in the β‐CD matrix exhibits blue phosphorescence emission under 260 nm excitation and yellow‐green phosphorescence emission under 360 nm excitation. It also maintains phosphorescence emission even at elevated temperatures (162 °C), a rare combination that significantly enhances functional diversity. The responsive nature of the biomass‐based system enables the dynamic regulation of room‐temperature phosphorescence (RTP) signals, supporting secure data processing.