Efficient Electroluminescence from New Lanthanide (Eu³⁺, Sm³⁺) Complexes

Abstract

The syntheses, structures, and electroluminescent properties are described for two new lanthanide complexes Ln(HFNH)3phen [HFNH = 4,4,5,5,6,6,6-heptafluoro-1-(2-naphthyl)hexane-1,3-dione; phen = 1,10-phenanthroline; Ln = Eu3+ (1), Sm3+ (2)]. Both complexes exhibit bright photoluminescence at room temperature (RT) due to the characteristic emission of Eu3+ and Sm3+ ion. Several devices using the two complexes as emitters were fabricated. The performances of these devices are among the best reported for devices using europium complex and samarium complex as emitters. The device based on 1 with the structure ITO/TPD (50 nm)/1:CBP (10%, 40 nm)/BCP (20 nm)/AlQ (30 nm)/LiF (1 nm)/Al (200 nm) exhibits the maximum brightness of 957 cd/m2, current efficiency of 4.14 cd/A, and power efficiency of 2.28 lm/W with a pure red Eu3+ ion emission. Especially, at the high brightness of 200 cd/m2, the device of 1 still has a high current efficiency of 2.15 cd/A. The device of 2 with a three-layer structure of ITO/TPD (50 nm)/2 (50 nm)/BCP (20 nm)/LiF (1 nm)/Al (200 nm) gives the maximum brightness of 42 cd/m2, current efficiency of 0.18 cd/A. By the comparison of the electroluminescent properties of devices based on Eu(TTA3phen (TTA = 2-thenoyltrifluoroacteonate) and 1, we conclude that the polyfluoration on the alkyl group of the ligand and the introduction of the long conjugate naphthyl group into the ligand improve the efficiency of 1-doped devices, especially at high current densities.

Layered exfoliable crystalline materials based on Sm-, Eu- and Eu/Gd-2-phenylsuccinate frameworks. Crystal structure, topology and luminescence properties

“…Particularly, their luminescence properties that enable these materials to be employed as sensors 1 , optical fiber lasers and amplifiers 2 , molecular thermometers 3 and electroluminescent materials 4 have received increasing attention. 5 MOFs offer a unique platform and methodology for the development of luminescent lanthanide materials not only because of some well described synthesis methods and resulting porosities, but also for certain degree of structural tenability.…”

Ionic liquid as plasticizer for europium(iii)-doped luminescent poly(methyl methacrylate) films

“…[1][2][3][4][5][6][7] Processable lanthanide-based luminescent molecular materials can be obtained by doping the lanthanide(III) complex in a polymer matrix. 8,9 Typical applications of such polymer films are in organic light emitting diodes (OLEDs) [10][11][12][13][14] or in active optical polymer fibers for data transmission. [15][16][17] A popular polymer matrix for use as host for luminescent lanthanide complexes is poly-(methyl methacrylate) (PMMA), which is transparent at wavelengths longer than 250 nm.…”

Highly Improved Electroluminescence from a Series of Novel EuIII Complexes with Functional Single‐Coordinate Phosphine Oxide Ligands: Tuning the Intramolecular Energy Transfer, Morphology, and Carrier Injection Ability of the Complexes

“…[1][2][3][4][5][6][7][8] However, for many reasons the electroluminescence (EL) performance of these lanthanide materials is still much lower than what people expect. The unbalanced hole and electron injection and transport should be one of the most important factors.…”