A porphyrin pentamer as a bright emitter for NIR OLEDs

Journal article

The luminescence and electroluminescence of an ethyne-linked zinc(II) porphyrin pentamer have been investigated, by testing blends in two different conjugated polymer matrices, at a range of concentrations. The best results were obtained for blends with the conjugated polymer PIDT-2TPD, at a porphyrin loading of 1 wt%. This host matrix was selected because the excellent overlap between its emission spectrum and the low-energy region of the absorption spectrum of the porphyrin oligomer leads to efficient energy transfer. Thin films of this blend exhibit intense fluorescence in the near-infrared (NIR), with a peak emission wavelength of 886 nm and a photoluminescent quantum yield (PLQY) of 27% in the solid state. Light-emitting diodes (LEDs) fabricated with this blend as the emissive layer achieve average external quantum efficiencies (EQE) of 2.0% with peak emission at 830 nm and a turn-on voltage of 1.6 V. This performance is remarkable for a singlet NIR-emitter; 93% of the photons are emitted in the NIR (λ > 700 nm), indicating that conjugated porphyrin oligomers are promising emitters for non-toxic NIR OLEDs.

Authors: Tejerina, L; Rapidis, AG; Rickhaus, M; Murto, P; Genene, Z

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Journal of Materials Chemistry C
• Volume: 10
• Issue: 15
• Pages: 5929-5933
• Place of publication: England
• Publication date: 2022-03-14
• Acceptance date: 2022-03-06
• DOI: 10.1039/d1tc05951c
• EISSN: 2050-7534
• ISSN: 2050-7526
• Pmid: 35517642
• Language: English
• Keywords: FFR