6533b7d1fe1ef96bd125cd76
RESEARCH PRODUCT
Efficient Green Light-Emitting Electrochemical Cells Based on Ionic Iridium Complexes with Sulfone-Containing Cyclometalating Ligands
Henk J. BolinkCatherine E. HousecroftEdwin C. ConstableDaniel TorderaJosé M. Junquera-hernándezEnrique OrtíJennifer A. ZampeseAndreas M. BünzliAntonio Pertegássubject
PhotoluminescenceLigandOrganic ChemistrySubstituentchemistry.chemical_elementIonic bonding02 engineering and technologyGeneral ChemistryPyrazole010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciencesCatalysis0104 chemical sciencesSulfonechemistry.chemical_compoundchemistryMolecular orbitalIridium0210 nano-technologydescription
A new approach to obtain green-emitting iridiumA complexes is described. The synthetic approach consists of introducing a methylsulfone electron-withdrawing substituent into a 4-phenylpyrazole cyclometalating ligand in order to stabilize the highest- occupied molecular orbital (HOMO). Six new complexes have been synthe- sized incorporating the conjugate base of 1-(4-(methylsulfonyl)phenyl)-1 H- pyrazole as the cyclometalating ligand. The complexes show green emission and very high photoluminescence quantum yields in both diluted and concentrated films. When used as the main active component in light-emit- ting electrochemical cells (LECs), green electroluminance is observed. High efficiencies and luminances are obtained at low driving voltages. This approach for green emitters is an alter- native to the widely used fluorine- based substituents in the cyclometalat- ing ligands and opens new design possi- bilities for the synthesis of green emit- ters for LECs.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-05-06 | Chem. Eur. J. |