Fig. 1. Schematic fabrication process of Cot-PLN

Fig. 2. ATR-IR spectra of Cotton, Cot-PMAPS, and Cot-PLN

Fig. 3. TG curves of cotton (a), Cot-PMAPS (b), and Cot-PLN (c); DTG curves of Cotton (d), Cot-PMAPS (e), and Cot-PLN (f)

Fig. 4. XRD patterns of Cotton, Cot-PMAPS, and Cot-PLN

Fig. 5. SEM images of Cotton, Cot-PMAPS, and Cot-PLN, the EDS images of Cot-PLN

Fig. 6. Optical photos of Cotton, Cot-PMAPS, and Cot-PLN

Fig. 7. Decay curves of the illuminance under 10 min (a) and 24 h (b) irradiation by fluorescent lamps

Fig. 8. Decay curves of the illuminance under 10 min (a) and 24 h (b) irradiation by UV

Fig. 9. Reusability test on Cot-PLN in terms of persistent luminescence

Fig. 10. Optical pictures of logo with persistent luminescence