Recent progress in research on stimuli-responsive circularly polarized luminescence based on π-conjugated molecules

Abstract

This short review article summarizes recent progress in research on various stimuli-responsive circularly polarized luminescence (CPL) properties derived from π-conjugated molecules and related materials. As representative examples, assembled structures of chiral π-conjugated polymers and molecules showed tunable CPL resulting from the enhancement of chirality induction by aggregation. Fascinating CPL-active species, pyrrole-based anionresponsive π-conjugated molecules exhibiting CPL induced by anion binding and ion pairing, are also discussed.

Circularly Polarized Luminescence Switching in Small Organic Molecules

“…Therefore, a main goal is to design new structures to obtain emission property combing high Φ F and g lum . At the same time, the CPL switching (i.e., inversion of handedness, the on/off switching, and the shift of emission wavelength), which can be triggered by the external stimuli such as light, solvent, pressure and ions, is becoming an important topic . The CPL‐switchable SOMs are expected to find promising applications in security technologies and sensing devices, which promoted us to review the recent progress in this field.…”

“…In addition to the assembly structure, other factors, such as excimer formation, conformation of monomeric fluorophores, electronic nature of π‐conjugated skeleton or peripheral substituent, and intramolecular charge‐transfer (CT) dynamics, may also exhibits significant influences on the CPL properties. Our discussion will focus on the strategies to tune the factors that influence CPL properties, which is expected to complement well the recent review about polymers and SOMs displaying stimuli‐responsive CPL …”

enantio-Enriched CPL-active helicene–bipyridine–rhenium complexes

“…It would therefore be of great interest to develop chiral analogues 6 in order to benefit from the chiral version of emission, namely circularly polarized luminescence (CPL) which may potentially be used in cryptography or for 3D-displays. 7,8 …”

Helically assembledπ-conjugated polymers with circularly polarized luminescence

“…For the purpose of functionalizing CPL, it is very interesting to control chiroptical properties, especially CPL, through the use of external stimuli [70]. …”