Related Experiment Video
Updated: May 26, 2026
10:33
An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation
Published on: February 27, 2019
High-Contrast Handedness Inversion in Circularly Polarized Organic Ultralong Phosphorescence Enabled by an
Chi-Bo Feng1, Juan Wei2, Jiao Liu1
1College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, China.
Advanced Materials (Deerfield Beach, Fla.)
|May 25, 2026
Summary
Researchers developed a novel film for dynamic control of circularly polarized ultralong room-temperature phosphorescence (CP-OURTP). This breakthrough enables reversible switching of chiroptical properties for advanced photonic applications.
Area of Science:
- Materials Science
- Photonics
- Organic Chemistry
Background:
- Dynamic and reversible control of circularly polarized ultralong room-temperature phosphorescence (CP-OURTP) is crucial for time-gated chiroptical photonics.
- Achieving simultaneous handedness inversion and large dissymmetry factors is challenging due to net-chirality cancellation and photonic bandgap (PBG) collapse.
Purpose of the Study:
- To develop a CP-OURTP material with dynamic and reversible control of chiroptical properties.
- To overcome the limitations of PBG collapse during handedness inversion.
Main Methods:
- Fabrication of a decoupled bilayer CP-OURTP film.
- Coupling a phosphorescent polymer emitter with a photoresponsive chiral helical superstructure (CHS).
- Utilizing an antagonistic chirality-offset design with a chiral photoswitch and an oppositely handed static dopant.
Main Results:
- The film demonstrated reversibly switchable luminescence dissymmetry factors (glum) up to ±1.0.
- Achieved a phosphorescence quantum yield of 21.4% and an ultralong lifetime up to 388 ms.
- Exhibited stable operation over 50 switching cycles and maintained PBG-emission overlap during inversion.
Conclusions:
- The developed CHS-engineering strategy enables on-demand chiroptical control for CP-OURTP materials.
- This approach provides a general route for creating materials with reversible handedness switching.
- Applications include high-fidelity rewritable anti-counterfeiting labels and multi-level information encryption.
Related Concept Videos
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
01:26Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
02:24Properties of Enantiomers and Optical Activity
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
02:52Stereoisomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
02:30Chirality in Nature
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid. The...
02:25Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...