1 research outputs found
Red Luminescent Eu(III) Coordination Bricks Excited on Blue LED Chip
Three types of red
luminescent EuÂ(III) complexes with Schiff base and hfa ligands (hfa:
hexafluoroacetylacetonate), mononuclear [EuÂ(hfa)<sub>2</sub>(OAc)Â(salen)<sub>2</sub>] (OAc: acetate anion, salen: <i>N,N</i>′-bisÂ(salicylidene)Âethylenediamine),
brick-type [Eu<sub>2</sub>(hfa)<sub>4</sub>(OAc)<sub>2</sub>(salbn)<sub>2</sub>] (salbn: <i>N,N</i>′-bisÂ(salicylidene)-1,4-butanediamine),
and polynuclear [EuÂ(hfa)<sub>2</sub>(OAc)Â(salhen)]<sub><i>n</i></sub> (salhen: <i>N,N</i>′-bisÂ(salicylidene)-1,6-hexanediamine)
are reported for white light-emitting diode (LED) devices. Among these
complexes, brick-type [Eu<sub>2</sub>(hfa)<sub>4</sub>(OAc)<sub>2</sub>(salbn)<sub>2</sub>] excited by blue light (460 nm) exhibits the
photosensitized quantum yield (Φ<sub>π–π*</sub> = 47%) and remarkably high efficiency of sensitization (η<sub>sens</sub> = 96%). The efficiency of sensitization is caused by the
excited state based on ligand–ligand interaction between the
Schiff base and hfa ligands in EuÂ(III) complexes. To fabricate LED
devices, the red luminescent [Eu<sub>2</sub>(hfa)<sub>4</sub>(OAc)<sub>2</sub>(salbn)<sub>2</sub>] was mounted on an InGaN blue LED chip