Related Experiment Video
Updated: Jan 9, 2026

Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
Hydrogen-bonding environment suppresses thermally activated delayed fluorescence
Sushree Suhani Puhan1, Laxmipriya Dash2,3, Palas Roy1
1Department of Chemistry, IIT Bhubaneswar Argul 752050 India palasroy@iitbbs.ac.in.
Abstract:
Thermally activated delayed fluorescence (TADF) is a promising innovation in display technology where the nonemissive triplet excitons can be thermally converted back into emissive singlet excitons through reverse intersystem crossing. Organic TADF emitters often feature donor-acceptor (D-A) architectures, whose conformations critically influence emission dynamics and efficiency. Introducing intramolecular hydrogen-bonding between D and A moieties is an emerging strategy to rigidify the structure and improve TADF emission. However the influence of environmental factors on such hydrogen-bonding interactions remains unclear. Here we investigate the impact of the hydrogen-bonding medium on TADF emission using steady-state and time-resolved emission spectroscopy. Protic solvents universally quench TADF emission, correlating with reduced prompt emission lifetimes, while delayed lifetimes remain largely unchanged. A clear kinetic isotope effect unequivocally confirms that solvent protons directly participate in hydrogen-bonding interactions with the photoexcited emitter, thereby perturbing its excited-state energetics. Ultrafast spectroscopy reveals a picosecond D-to-A intramolecular charge transfer event that slows in viscous media indicating a D-A torsional relaxation. The relaxation time further slows in a protic environment highlighting the role of solvent-emitter hydrogen-bonding interactions resulting in unfavourable excited state D-A conformations and diminished emission. These findings underscore the importance of microenvironment control in designing efficient TADF emitters for display applications and photocatalysis.
More Related Videos
08:51Scale-up Chemical Synthesis of Thermally-activated Delayed Fluorescence Emitters Based on the Dibenzothiophene-S,S-Dioxide Core
Published on: October 24, 2017
11:27Single-Molecule Förster Resonance Energy Transfer Methods for Real-Time Investigation of the Holliday Junction Resolution by GEN1
Published on: September 18, 2019
Related Concept Videos
Variables Affecting Phosphorescence and Fluorescence
Hydrogen Bonds
Hydrogen Bonds
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
Deactivation Processes: Jablonski Diagram
Photoluminescence: Fluorescence and Phosphorescence
A pair of electrons in a...
Photoluminescence: Applications