Reversible humidity-responsive room-temperature phosphorescence with tunable afterglow color via TS-FRET in tryptophan derivative-doped PVA films.

Authors

Hao Luo, Yuexia Luo, Hongtao Nie, Qiusheng Wang

Published in

Analytical methods : advancing methods and applications. Nov 12, 2026. Epub Nov 12, 2026.

Abstract

Developing humidity-responsive organic room-temperature phosphorescence (RTP) materials with long lifetimes and tunable colors remains challenging. We report a series of RTP films based on halogenated Fmoc-L-tryptophan derivatives doped into poly(vinyl alcohol) (PVA). These films show ultralong phosphorescence lifetimes up to 3.68 s and blue afterglow lasting over 31 s under ambient conditions. By adding Rhodamine B as an energy acceptor, triplet-to-singlet Förster resonance energy transfer enables systematic color tuning from blue to orange. Spectroscopic and NMR analyses confirm that intermolecular hydrogen bonding between the tryptophan derivatives and PVA stabilizes the triplet excited states. Notably, RTP emission can be reversibly switched off by water fuming and restored by heating, due to disruption and reformation of the rigid hydrogen-bonding network. This moisture response is further demonstrated in LED chips showing quenchable and recoverable multicolor afterglow. Our findings offer a simple strategy for humidity-responsive RTP materials with tunable colors, long lifetimes, and good reversibility, promising for humidity sensing and anti-counterfeiting.

PMID:
43016205
Bibliographic data and abstract were imported from PubMed on 12 Nov 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.