Highly fluorinated erbium(III) complexes for emission in the C-band

Abstract

Two highly fluorinated Er 3+ complexes with three 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5octanedionate (fod) groups and either bipyridine (bipy) or bathophenantholine (bath) as the ancillary ligand emitting at the C-band (third communication window for fiber transmission) are presented. These complexes are the result of a design process aimed at decreasing the vibrational quenching from high frequency oscillators. The structure of [Er(fod) 3 (bipy)] has been elucidated by single-crystal X-ray diffraction, while Sparkle/PM6 and Sparkle/PM7 semi-empirical calculations have been used to model the ground state geometry for [Er(fod) 3 (bath)]. Photoluminescence studies confirm sensitization of the Er 3+ ions by antenna effect, leading to NIR emission at 1.53 µm. This energy transfer proves to be more efficient for [Er(fod) 3 (bath)] as a result of the bulkier and more rigid structure of bath diimide. The good thermal stability of the materials up to over 200 ºC allows envisaging their use in erbium-doped waveguides, NIR-OLEDs or other optoelectronic devices.

Lanthanoid/Alkali Metal β‐Triketonate Assemblies: A Robust Platform for Efficient NIR Emitters

“…The [Er(Ae ⋅ HOEt)( L ) 4 ] 2 (Ae + =Na + , K + and Rb + ) assemblies also display fluorescent NIR emission in the λ =1420 to 1620 nm range, which is attributed to the characteristic 4 I 15/2 ← 4 I 13/2 transition (Figure 5). The band appears narrow and structured as a result of crystal field effects 26. Again, the structure of the emission band varies slightly due to the relatively different crystal field effects present in the three assemblies.…”

“…Attempts to remove such quenching pathways include the synthesis of ligands with fewer of these high‐frequency oscillators19–21 and dissolution of lanthanoid complexes in deuterated solvents 22. 23 Strategies such as perfluorination and quantitative deuteration of ligands have been explored successfully to minimize the extent of quenching and improve the NIR emission of lanthanoid complexes,24, 25 especially in the case of ligands that belong to the β‐diketonate class 26–29. Lanthanoid β‐diketonate complexes have been proven to be robust, thermally stable, and suitable for applications in materials science 30–32.…”

“…[22,23] Strategies such as perfluorination and quantitative deuteration of ligands have been explored successfully to minimize the extent of quenching and improvet he NIR emissiono fl anthanoid complexes, [24,25] especiallyi nt he case of ligandst hat belong to the b-diketonate class. [26][27][28][29] Lanthanoid b-diketonate complexes have been provent ob er obust, thermally stable, and suitable for applications in materials science. [30][31][32] However,s ynthetic routes towards perfluorinated li-gands are significantly more complicated and somewhat hinder ligand design,a nd deuteration facilities are not routinely accessible within synthetic chemistry laboratories.…”

Synthesis, Photoluminescence and Effect of Lanthanide Contraction on Structures of 3D Lanthanide‐Organic Frameworks from 1,4‐Benzenedicarboxylic Acid and Oxalic Acid

“…The diffused reflectance spectra of the compounds 1–6 along with the free ligands are shown in Figure . The H 2 BDC displayed a broad absorption band in the UV region from 200 to 350 nm peaking around 325 nm, attributed to π→π* transitions of the organic ligand . The spectra of compounds 1–6 are similar to the ones observed for the free ligands, implying that the singlet excited state of the free ligand is not significantly affected by the coordination of the Ln 3+ ion .…”

Opportunities for Low Cost Processing of Erbium 8-Quinolinolates for Active Integrated Photonic Applications

“…Er-doped organic materials showed promising features as amorphous infrared emitters. [7][8][9] In particular, erbium(III) tris (8-hydroxyquinoline), also known as erbium quinoline (ErQ), and derivatives are * Author to whom correspondence should be addressed. still subject of an intensive study for their good emission efficiency, improved by chemical synthesis methods aimed at the reduction of the quenching of the infrared radiation.…”