Simple Vanilla Derivatives for Long-Lived Room-Temperature Polymer Phosphorescence as Invisible Security Inks
Phosphorescence spectra, powder XRD patterns, and FT-IR spectra. (a) Phosphorescence decay profiles of M1-M4-doped PVA. (b) CIE diagram for the emission spectra of M2 and M2-acid-doped PVA. (c,d) Phosphorescence emission spectra of the M1-doped PVA film with cooling and heating processes (). (e) Powder XRD patterns of the M1-doped PVA film at heating conditions. (f) FT-IR spectra of these vanilla-doped PVA films.