Montes, Victor A. published the artcileUltrafast Dynamics of Triplet Excitons in Alq3-Bridge-Pt(II)porphyrin Electroluminescent Materials, Formula: C20H28B2O4S2, the publication is Journal of the American Chemical Society (2007), 129(42), 12598-12599, database is CAplus and MEDLINE.
Excited-state dynamics are crucial for maximizing the performance of organic light-emitting diodes (OLEDs). Because electron-hole recombination yields singlet and triplet excited states in a 3:1 ratio, it is important to harvest the energy of triplets in light-emitting processes. Self-assembled multichromophore electroluminescent materials consisting of a trisquinolinolate Al(III) (Alq3) donor, fluorene-based conjugated oligomers as a bridge, and Pt(II) tetraphenylporphyrin as an acceptor and phosphorescent emitter are described. In these materials, the energy of singlet as well as triplet states is harvested and emitted as red phosphorescence from the porphyrin acceptor. Attention was devoted to the triplet exciton dynamics, which was studied by ultrafast transient spectroscopy, and the observations are compared with phosphorescence in thin films and with electroluminescence from OLEDs. Exothermicity of the forward Alq3-to-fluorene bridge triplet transfer appears to be a less stringent requirement for triplet transfer electroluminescence. In contradistinction, the energy alignment between the bridge and Pt(II)porphyrin emitter is of crucial importance. The triplet exciton dynamics has a dominant effect on the electroluminescence properties of conjugated donor-bridge-acceptor materials. The triplet-energy transfer operates on an ultrafast time scale (kTTET = (4-6) × 1010 s-1) and requires careful energy alignment of the components (3ΔED-B ≈ 3ΔEB-A ≥ 0.1 eV) to prevent endothermic energy transfer and severe quenching of the electroluminescence. This is the 1st time triplet dynamics was directly observed in donor-acceptor electroluminescent materials and direct connection to device efficiency was established.
Journal of the American Chemical Society published new progress about 239075-02-6. 239075-02-6 belongs to alcohols-buliding-blocks, auxiliary class Thiophene,Boronic acid and ester,Boronate Esters, name is 5,5′-Bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,2′-bithiophene, and the molecular formula is C20H28B2O4S2, Formula: C20H28B2O4S2.
Referemce:
https://en.wikipedia.org/wiki/Alcohol,
Alcohols – Chemistry LibreTexts