Fig. 3: Photophysical properties of the 4TPYBOH@PVA–Eu films.

a UV–vis absorption spectra, b Fluorescence spectra, c Phosphorescence spectra, and d phosphorescence-decay profiles of 4TPYBOH@PVA–Eu films that were prepared by being immersed in different Eu3+(aq) (0.1–20 mg/mL). e Simplified Jablonski diagram for explaining RTP manipulation based on ET.