Thermally activated delayed fluorescence (TADF) organic molecules for efficient X-ray scintillation and imaging
Source abstract
Abstract
X-ray detection, which plays an important role in medical and industrial fields, usually relies on inorganic scintillators to convert X-rays to visible photons; although several high-quantum-yield fluorescent molecules have been tested as scintillators, they are generally less efficient. High-energy radiation can ionize molecules and create secondary electrons and ions. As a result, a high fraction of triplet states is generated, which act as scintillation loss channels. Here we found that X-ray-induced triplet excitons can be exploited for emission through very rapid, thermally activated up-conversion. We report scintillators based on three thermally activated delayed fluorescence molecules with different emission bands, which showed significantly higher efficiency than conventional anthracene-based scintillators. X-ray imaging with 16.6 line pairs mm-1 resolution was also demonstrated. These results highlight the importance of efficient and prompt harvesting of triplet excitons for efficient X-ray scintillation and radiation detection.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Luminescence and Fluorescent Materials · Lanthanide and Transition Metal Complexes · Organic Light-Emitting Diodes Research
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (46)
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