posted on 2021-09-20, 16:06authored byJun Feng, Zijian Gu, Wenyue Ma, Shan Jiang, Yang Jiao, Leijing Liu, Bin Xu, Wenjing Tian
Circularly
polarized luminescence (CPL) materials have potential
applications in 3D optical displays, information security encryption,
sensors, and photoelectric devices because of their inherent advantages
of tunable emission, high solid-state fluorescence quantum efficiency,
and abundant species. Herein, we construct CPL supermolecular assembly
with acid stimuli response by assembling a typical aggregation induced
emission (AIE) molecule 9,10-bis(4-pyridyl)anthracene (BP4VA) with
a self-assembled chiral molecule 1,3,5-trimesyltrilglutamic acid hexaethyl
ester (TMGE). Scanning electron microscope (SEM), transmission electron
microscope (TEM), and fluorescence images proved the successful assembly
of BP4VA and TMGE. The fluorescent emission peak of the assembly was
the same as that of BP4VA in solution, but the intensity was significantly
stronger than that of BP4VA in solution due to the aggregation of
BP4VA in the assembly. Circular dichroism (CD) spectra of the supermolecular
assembly indicate that the chirality can be passed from the chiral
molecule TMGE to the achiral AIE molecule BP4VA through the coassembly.
The CPL wavelength of the assembly achieves a red-shift after the
stimuli of trifluoroacetic acid (TFA) because of the protonation of
pyridine on BP4VA, while the morphology of the assembly has no big
difference before and after protonation. The study provides an effective
strategy to prepare stable acid stimulus responsive CPL materials
through the assembly of AIE molecules.