10.1021/acsami.5b08402.s001
Xudong Yu
Xudong
Yu
Xiaoting Ge
Xiaoting
Ge
Haichuang Lan
Haichuang
Lan
Yajuan Li
Yajuan
Li
Lijun Geng
Lijun
Geng
Xiaoli Zhen
Xiaoli
Zhen
Tao Yi
Tao
Yi
Tunable
and Switchable Control of Luminescence through
Multiple Physical Stimulations in Aggregation-Based Monocomponent
Systems
American Chemical Society
2015
switchable control
Multiple Physical Stimulations
fluorescence changes
emissive
gelation
mechanochromic
gelator
emission
fluorescence intensity quenching
ICT
luminescence
stimuli
naphthalimide
2015-11-04 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Tunable_and_Switchable_Control_of_Luminescence_through_Multiple_Physical_Stimulations_in_Aggregation_Based_Monocomponent_Systems/2113468
This
report describes how the luminescence of naphthalimide could
be tuned by various physical stimuli, including heat, sonication,
and grinding. Herein, instant and switchable control of color and
fluorescent emissions has been achieved by the sonication-triggered
gelation of an organic liquid with naphthalimide-based organogelators
(<b>N3</b>–<b>N7</b>). Green emissive suspensions
of the gelators in organic liquids are transformed into orange emissive
gels upon brief irradiation with ultrasound with an emission wavelength
red-shift of approximately 60 nm and fluorescence intensity quenching
by a factor of 20, which can subsequently be reversed by heating.
When sonication-triggered S-gels are evaporated to S-xerogels, the
solid state xerogels (<b>N3</b>, <b>N4</b>, <b>N6</b>, <b>N7</b>) exhibit mechanochromism, the color of which changes
from red to yellow and the emission color of which changes from orange
to green with enhanced intensity by grinding. This mechanochromic
property can be reversed through a regelation process. The mechanochromic
character of the S-xerogel of <b>N3</b> is thus applied to quantitatively
sense the mechanical pressure range from 2 to 40 MPa through fluorescence
changes, reflecting a new type of application for gelation assembly.
The physical stimuli triggered fluorescence changes of these compounds
strongly depend on the molecular structure and solvent. The results
demonstrate that the different aggregation modes and long-range order
arrangement of the molecules regulated by the stimulus may affect
the internal charge transfer (ICT) process of the naphthalimide groups,
resulting in the tunability of the photophysical properties of the
gelators. This report provides a new strategy for tunable and switchable
control of luminescence through nonchemical stimuli in aggregation-based
monocomponent systems.