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Circularly polarized luminescence (CPL) has numerous applications in optical data storage, quantum computing, bioresponsive imaging, liquid crystal displays, and backlights in three-dimensional (3D) displays. In addition to their competitive optical properties, carbon dots (CDs) benefit from simple and low-cost preparation, facile post-modification, and excellent resistance to photo- and chemical bleaching after carbonization. Combining the superior optical performance with polarization peculiarities through hierarchical structure engineering is imperative for the development of CDs. In this study, hydrophobic interactions of aromatic ligands, which participate in the surface-ligand post-modification process on the ground-state chiral carbon core, are employed to drive the oriented assembly. Furthermore, the residual chiral amides on CDs form multiple hydrogen bonds during gradual aggregation, causing the assembled materials to form an asymmetric bending structure. Superficial ligands interfere with the optical dynamics of the exciton radiation transition and stabilize the excited state of the assembled materials to achieve a circularly polarized signal. The linkage ligands overcome the frequent aggregation-induced quenching phenomenon that present difficulties in conventional CDs, facilitate the assembly of self-supporting films, and improve chiral optical expression. The full-color and white CPL are manipulated by simply adjusting the functional groups of the ligands, which also illustrates the versatility of the post-modification strategy. Finally, large chiral flexible films and multicolor chiral light-emitting diodes based on the stable chiral powder phosphors were constructed, thereby providing feasible materials and technical support for flexible 3D displays., (© 2024 Wiley-VCH GmbH.)

The synthesis of a family of chiral and enantiomerically pure pyridyl-diamide (pda) ligands that upon complexation with europium [Eu(CF 3 SO 3 ) 3 ] result in chiral complexes with metal centered luminescence is reported; the sets of enantiomers giving rise to both circular dichroism (CD) and circularly polarized luminescence (CPL) signatures. The solid-state structures of these chiral metallosupramolecular systems are determined using X-ray diffraction showing that the ligand chirality is transferred from solution to the solid state. This optically favorable helical packing arrangement is confirmed by recording the CPL spectra from the crystalline assembly by using steady state and enantioselective differential chiral contrast (EDCC) CPL Laser Scanning Confocal Microscopy (CPL-LSCM) where the two enantiomers can be clearly distinguished., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Next-generation medical and consumer electrical devices require soft, flexible materials. Piezoelectric materials, capable of converting mechanical stress into electrical energy, are of interest across various fields. Chiral nanostructures, with inherent chirality, have emerged as potential piezoelectric materials. Peptide-based materials, known for self-assembly and stimuli responsiveness, hold promise for the utilization of chiral nanostructures. When combined with luminescent chromophores, peptides can generate aggregation-induced chiroptical effects like Circularly Polarized Luminescence (CPL) and Circular Dichroism (CD). In this study, a chiral organogel, L,L-1 is synthesized, and its self-assembly, mechanical properties, and chiroptical features are examined. The organogel exhibits thermo-reversible and thixotropic behavior, forming fibrillar networks and 2D-sheets upon cooling. CD spectroscopy reveals aggregation-induced chirality on pyrene chromophore, resulting in CPL with g lum values of 3.0 (± 0.2) × 10 -3 and 3.1 (± 0.2) × 10 -3 for L,L-1 and D,D-1, respectively. Notably, the 2D-sheets exhibit an enhanced piezoelectric response (d 33 ≈76.0 pm V -1 ) compared to the fibrillar network (d 33 ≈64.1 pm V -1 ). Introducing an electron-deficient molecule into the solution forms a Charge-transfer (CT) complex, modulating the piezoelectric response to d 33 ≈52.44 pm V -1 . This study offers a promising approach to optoelectronics design, presenting a chiral system with both CPL and piezoelectric responses, opening new possibilities for innovative applications., (© 2023 Wiley‐VCH GmbH.)

Efficient circularly polarized luminescence (CPL) from purely organic molecules holds great promise for applications in displays, sensing, and bioimaging. However, achieving high dissymmetry values (g lum ) from organic chromophores remains a significant challenge. Herein, we present a bioinspired approach using adenosine triphosphate (ATP)-triggered supramolecular polymerization of a naphthalene diimide-derived monomer (ANSG) to induce CPL with a remarkable g lum value of 1.1×10 -2 . The ANSG molecules undergo a templated, chiral self-assembly through a cooperative growth mechanism in the presence of ATP, resulting in scrolled nanotubes with aggregation-induced enhanced emission (AIEE) and induced CPL. Furthermore, we demonstrate the concept of chiroptical amplification of induced CPL by efficiently amplifying asymmetry using a mixture of chiral ATP and achiral pyrophosphate. This innovative approach opens numerous opportunities in the emerging field of circularly polarized luminescence., (© 2023 Wiley-VCH GmbH.)

Multiple heterohelicenes are a unique class of helical nonplanar scaffolds that have attracted great attention due to their appealing shapes, optical and electronic properties, and potential applications in chiral materials. This review describes the recent advances and challenges in the design and synthesis of representative multiple heterohelicenes with intriguing chiral properties. And the corresponding applications are also covered., (© 2022 Wiley-VCH GmbH.)

Molecular motions are closely associated with the behaviors and properties of organic materials. However, monitoring molecular motions is challenging. Herein, a chiral supramolecular system consisting of L-/D-phenylalanine (LPF/DPF) as a chiral inducer and an achiral tetraphenylethene derivative (TPEF) as a molecular rotor has been proposed and explored for real-time discriminating the supramolecular motions by the visualization of circularly polarized luminescence (CPL) signal variations. Derived from the ordered molecular motions of TPEF induced by LPF/DPF, highly organized aggregates have been progressively assembled in a controlled manner with differentiated morphologies, including spherical particles, one-dimensional fibers, and floor-shaped supercrystals. Notably, increasing level of ordered aggregates, in turn, led to quenching emissions, while the CPL signals have been dramatically amplified accompanying by a sharp enhancement of luminescence dissymmetry factors (g lum ) from nearly 0 to -0.1. The significant amplification of CPL is attributed to the ordered aggregates of supramolecules, leading to the decrease of electric transition dipole moments in supramolecular system. As a result of the chiral supramolecular motions powered by supramolecular crystallization, the supramolecular motions are conveniently discriminated by visual CPL signal variation with an enhancement of g lum value from 0 to -0.1 in real time., (© 2022 Wiley-VCH GmbH.)

Recently, scientists have reported a range of chiral fluorescence materials or chiral composites that can emit circularly polarized luminescence. Herein, two achiral metal-organic colloidal solutions were studied, showing active circularly polarized luminescence, which is observed in vortex stirring. The absolute values for g lum are 0.05 and 0.03 and the plus or minus sign of g lum depends on the colloidal structure and stirring direction, which make the property easy to manipulate. Further, the host-guest interaction study suggests both electrostatic interactions and coordination bonding may influence the chiroptical property from the colloidal solution to the guest molecule. Rhodamine 6G and its carboxylic acid derivative exhibit good quantum yields and acceptable g lum values in the colloidal solution., (© 2021 Wiley-VCH GmbH.)

Spirocyclic Ag 9 clusters, as a new form of intrinsically chiral metal clusters, were constructed through vertex-sharing of two in-situ-generated heteroaryl diide-centered metal rings. Such core-peripheral type clusters exhibit versatile photoluminescent and chiroptical behavior under different aggregation conditions. In contrast to a ligand-based fluorescence emission in a diluted solution of the clusters, a solvent polarity-caused assembly gives rise to new cluster-based phosphorous luminescence owing to radiative mode switching and aggregation-induced emission. Assembly of cluster enantiomers leads to micrometer-long helical nanofibers, whose handedness is determined by absolute configuration of individual spirocyclic clusters. Benefiting from exciton couplings of helical arrangements of chelating ligands at molecular and microscopic levels, the assembled film of cluster enantiomers exhibits circularly polarized luminescence with a high anisotropy factor (0.16)., (© 2020 Wiley-VCH GmbH.)

Controlling circularly polarized (CP) emission is key for both fundamental understanding and applications in the field of chiral photonics and electronics. Here, a completely new way to achieve this goal is presented. A luminescent thin film, made from a chiral conjugated phenylene bis-thiophenylpropynone able to self-assemble into ordered structures, emits highly circularly polarized light with opposite handedness from its two opposite faces. Such emergent nonreciprocal behavior in CP emission, so far unprecedented, represents a fundamental advance, opening new opportunities in design, preparation, and applications of CP emitting materials., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two new inherently chiral oligothiophenes characterized by the atropisomeric 3,3'-bithianaphtene scaffold functionalized with fused ring bithiophene derivatives, namely 4H-cyclopenta[2,1-b3:4b']dithiophene (CPDT) and dithieno[3,3-b:2',3'-d]pyrrole (DTP), were synthesized. The racemates were fully characterized and resolved into antipodes by enantioselective HPLC. The enantiomers were analyzed through different chiroptical techniques: electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) were employed to attribute the absolute configuration (AC). Comparison of experimental and calculated VCD spectra confirmed the DFT calculated conformational characteristics. The compound functionalized with two CPDT units was oxidized with FeCl 3 , and ECD and CPL of the resulting material were measured. Circularly polarized luminescence (CPL) was measured to verify if inherently chiral oligothiophenes could be promising systems for chiral photonics applications., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)