Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 1, Issue 3, Pages 567-574Publisher
AMER CHEMICAL SOC
DOI: 10.1021/am800124q
Keywords
blue electrophosphorescence; host; carbazole; triphenylsilyl substitution; trityl substitution; triplet energy; charge transport
Funding
- National Science Council
- Ministry of Economics of Taiwan
Ask authors/readers for more resources
Carbazole-based materials adopting the nonconjugated substitution of triphenylsilyl (-SiPh3) and trityl (-CPh3) side groups are studied as high-triplet-energy, morphologically, and electrochemically stable host materials with tunable carrier-transport properties for organic blue electrophosphorescence. The developed host materials 9-(4-tert-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole (CzSi), 9-(4-tert-butylphenyl)-3,6-ditrityl-9H-carbazole (CzC), and 9-(4-tert-butylphenyl)-3-(triphenylsilyl)-6-trityl-9H-carbazole (CzCSi) all show high triplet energies of 2.97-3.02 eV, along with high glass transition temperatures of 131 - 163 degrees C and superior electrochemical stability. Nevertheless, the carrier-transport properties show rather significant dependence on different substitutions, Although three different host materials give similar peak electroluminescence efficiencies at low driving currents, the CzSi host, which has more suitable carrier-transport properties, renders broadened distributions of the triplet excitons in phosphorescent devices, reducing the quenching associated with triplet-triplet annihilation and giving larger resistance against efficiency roll-off at higher brightnesses.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available