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Preprint_TADF-RTP_27.02.2020.pdf (1.08 MB)

N-Rich Electron Acceptor: Triplet Harvesting in Multichromophoric Pyridoquinoxaline and Pyridopyrazine-Based Organic Emitters

submitted on 27.02.2020, 19:25 and posted on 28.02.2020, 13:17 by BAHADUR SK, Samarth Sharma, Anto James, Subhankar Kundu, Abhijit Patra

Control of nonradiative deactivation of triplet states and tuning the singlet-triplet energy gap (ΔEST) are the major challenges to develop materials exhibiting thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP). Herein, we propose a new class of multichromophoric tridonor-acceptor (D3-A) compounds with rigid and flexible π-spacer having N-rich pyridoquinoxaline (PQ) and pyridopyrazine (PZ) acceptor core, respectively. The molecule with carbazole (Cz) donors at meta to quinoxaline (QX) nitrogen of rigid PQ core exhibits TADF. Whereas, the variation of the linkage position of Cz to PQ as well as twisted and flexible PZ core show predominantly RTP due to relatively higher singlet-triplet energy gap (ΔEST). Increasing the donor strength with phenoxazine (PO) in PZ system leads to simultaneous TADF and RTP. Further, we demonstrate the promising scope of all-organic triplet harvesting materials in solid-state security encryption.


BRNS, DAE (No. 37(2)/14/06/2016BRNS/37020)

Council of Scientific and Industrial Research (CSIR), New Delhi, (No. 01(2878)/17/EMR-II)


Email Address of Submitting Author


Indian Institute of Science Education and Research Bhopal



ORCID For Submitting Author


Declaration of Conflict of Interest

No conflict of interest

Version Notes