Highly efficient sensitized red emission from europium (III) in Ir-Eu bimetallic complexes by 3MLCT energy transfer.
Two novel iridium-europium bimetallic complexes, {[(dfppy)2Ir(mu-phen5f)]3EuCl}Cl2 and (dfppy)2Ir(mu-phen5f)Eu(TFAcA)3 [dfppy represents 2-(4',6'-difluorophenyl)-pyridinato-N,C(2'), phen5f stands for 4,4,5,5,5-pentafluoro-1-(1',10'-phenanthrolin-2'-yl)-pentane-1,3-dionate and TFAcA represents trifluoroacetylacetonate], were successfully synthesized. The novel ligand Hphen5f with four coordination sites was designed as a bridge to link the Ir (III) center and the Eu (III) center. The X-ray diffraction data shows that the nonbonding distances for Eu...Ir are 6.028, 5.907, and 6.100 A in the bimetallic complex {[(dfppy)2Ir(mu-phen5f)]3EuCl}Cl2. Photophysical studies implied that the high efficient red luminescence from the Eu (III) ion was sensitized by the (3)MLCT (metal-to-ligand charge transfer) energy based on an Ir (III) complex-ligand in a d-f bimetallic assembly. The excitation window for the new bimetallic complex {[(dfppy)2Ir(mu-phen5f)]3EuCl}Cl2 extends up to 530 nm (1 x 10(-3) M in EtOH), indicating that this bimetallic complex can emit red light under the irradiation of sunlight.
Chen
Fang-Fang
FF
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Bian
Zu-Qiang
ZQ
Liu
Zhi-Wei
ZW
Nie
Dao-Bo
DB
Chen
Zhu-Qi
ZQ
Huang
Chun-Hui
CH
D003116:Color; D018360:Crystallography, X-Ray; D004735:Energy Transfer; D005063:Europium / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D010777:Photochemistry; D013053:Spectrophotometry
D007495:Iridium; D005063:Europium