Enhanced Resonance Energy Transfer and White-Light
Emission from Organic Fluorophores and Lanthanides in Dendron-based
Hybrid Hydrogel
- Publication date
- Publisher
Abstract
In this paper, we have investigated
the use of poly(aryl ether)
dendron-based gel as a medium for resonance energy transfer (RET)
from organic donors (phenanthrene, naphthalene, and pyrene) to lanthanide
[Eu(III) and Tb(III)] ions. The gel has been prepared through self-assembly
of glucose-cored poly(aryl ether) dendrons in a dimethyl sulfoxide/water
mixture (1:9 v/v). The efficiency of RET was calculated by metal-centered
emission quantum yield measurements in the gel medium. While there
was no resonance energy transfer observed between the donor–acceptor
pairs in solution, efficient RET has been observed in the gel medium.
The metal-centered quantum yield values were 11.9% for phenanthrene–Eu(III),
3.9% for naphthalene–Eu(III), and 3.6% for pyrene–Eu(III)
systems. Partial RET in the system has been utilized to generate white-light
emission from the gel by incorporating an additional lanthanide ion,
Tb(III), along with the organic donors and Eu(III). The CIE (Commission
Internationale d’Eclairage) coordinates obtained for gels formed
by phenanthrene–Tb(III)–Eu(III) (PTE), naphthalene–Tb(III)–Eu(III)
(NTE), and pyrene–Tb(III)–Eu(III) (PyTE) were (0.33,
0.32) for PTE, (0.35, 0.37) for NTE, and (0.35, 0.33) for PyTE. The
correlated color temperatures (CCT) for white-light-emitting gels
were calculated, and the values (5520 K for PTE, 4886 K for NTE, and
4722 K for PyTE) suggest that the system generates cool white light
