High-performance deep-blue emitters that meet the BT.2020 standard proposed by the International Telecommunication Union(ITU)for organic light-emitting diodes(OLEDs)remain highly limited.In this work,four deep-blue em...High-performance deep-blue emitters that meet the BT.2020 standard proposed by the International Telecommunication Union(ITU)for organic light-emitting diodes(OLEDs)remain highly limited.In this work,four deep-blue emitters,PP1M,PP2M,PP3M,and PP4M,are designed and synthesized by connecting methylsubstituted biphenyl groups with classical hot exciton building block of phenanthreneimidazole.The introduction of methyl groups contributes to increase the molecular torsion angle and widen the energy gaps for the four compounds.Through appropriate modulation of substitution site,PP3M achieves the highest photoluminescence quantum yield of 85.3%in neat film.As a result,the PP3M-based device exhibits deep-blue light with external quantum efficiency of 7.2%and suppressed efficiency roll-off.The device also shows a small full width at half maximum of 53 nm and the CIE coordinates locate at(0.16,0.04),meeting well with the BT.2020 standard.The high exciton utilization efficiency is primarily ascribed to the hot exciton pathway.This study provides a reliable insight for the design of efficient deep-blue OLEDs with high color purity.展开更多
An efficient method for the preparation of indolin-3-one derivatives from 2-alkynylnitrobenzenes and indoles under alkaline conditions is described.In this reaction,the Wittig process is initiated by PPh_(3),and then ...An efficient method for the preparation of indolin-3-one derivatives from 2-alkynylnitrobenzenes and indoles under alkaline conditions is described.In this reaction,the Wittig process is initiated by PPh_(3),and then the indole is activated under the action of the base to offer the indolin-3-one substituted by C(2)-indole in up to 98%yield.A variety of functionalized indolin-3-one derivatives were synthesized by modification of 2-alkynylnitroarenes under transition-metal free conditions.展开更多
文摘High-performance deep-blue emitters that meet the BT.2020 standard proposed by the International Telecommunication Union(ITU)for organic light-emitting diodes(OLEDs)remain highly limited.In this work,four deep-blue emitters,PP1M,PP2M,PP3M,and PP4M,are designed and synthesized by connecting methylsubstituted biphenyl groups with classical hot exciton building block of phenanthreneimidazole.The introduction of methyl groups contributes to increase the molecular torsion angle and widen the energy gaps for the four compounds.Through appropriate modulation of substitution site,PP3M achieves the highest photoluminescence quantum yield of 85.3%in neat film.As a result,the PP3M-based device exhibits deep-blue light with external quantum efficiency of 7.2%and suppressed efficiency roll-off.The device also shows a small full width at half maximum of 53 nm and the CIE coordinates locate at(0.16,0.04),meeting well with the BT.2020 standard.The high exciton utilization efficiency is primarily ascribed to the hot exciton pathway.This study provides a reliable insight for the design of efficient deep-blue OLEDs with high color purity.
文摘An efficient method for the preparation of indolin-3-one derivatives from 2-alkynylnitrobenzenes and indoles under alkaline conditions is described.In this reaction,the Wittig process is initiated by PPh_(3),and then the indole is activated under the action of the base to offer the indolin-3-one substituted by C(2)-indole in up to 98%yield.A variety of functionalized indolin-3-one derivatives were synthesized by modification of 2-alkynylnitroarenes under transition-metal free conditions.
