Structure-Property Relationship in Amber Color Light-Emitting Electrochemical Cell with TFSI Counteranion: Enhancing Device Performance by Different Substituents on N boolean AND N Ligand


Demir N., Karaman M., Yakali G., ARİFİOĞLU T. , DENİZALTI S., DEMİÇ Ş., ...Daha Fazla

INORGANIC CHEMISTRY, cilt.60, sa.7, ss.4410-4423, 2021 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 60 Konu: 7
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1021/acs.inorgchem.0c02939
  • Dergi Adı: INORGANIC CHEMISTRY
  • Sayfa Sayıları: ss.4410-4423

Özet

Amber color emitting novel Ir(III) complexes were synthesized: [Ir-(Meppy)(2)( Fpbpy)][ PF6] ( 1bPF6), [Ir(Meppy) 2( Fpbpy)][TFSI] ( 1bTFSI), [Ir(Meppy)(2)(MeObpy)][PF6] (2bPF6) and [Ir(Meppy)2(MeObpy)][TFSI] (2bTFSI), where Meppy = 2-(p-methylphenyl)-pyridine (b), Fpbpy = 4,4'-bis(4-fluorophenyl)-2,2'-bipyridine (1), and MeObpy = 4,4'-bis(4-methoxy)-2,2'-bipyridine (2). The photophysical and X-ray results showed that the complexes have aggregation-induced phosphorescent emission (AIPE) and a salt-induced polymorphism effect. The highest photoluminescence intensity was observed in complex 2bTFSI compared to other complexes in the solid state. Their theoretical absorption and phosphorescence emission transitions in acetonitrile were also investigated by using double- and triple-. basis sets with B3LYP and PBE0 hybrid functional. The best lightemitting electrochemical cell (LEC) performance was exhibited by complex 2bTFSI, and the data obtained were as follows: Luminance, current density, luminous efficiency, turn-on time, power efficiency, and external quantum efficiency were measured as 16 156 cd/m2, 554 mA/cm(2), 8.49 cd/A, 17 s, 3.95 lm/W and 6.37%, respectively. The investigation of crystallographic characteristics have shown that the LEC performance of these complexes depends on cationic-anionic interaction which has a significant influence on molecular stacking of the molecules. Because, complex 2bTFSI, with weak cationic-anionic interactions, shows strong p center dot center dot center dot p stacking interactions between the adjacent molecules, it is the best lighting application candidate among the complexes.