There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（...There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（4,6-diphenyl-l,3,5-triazin-2-yl）phenyl）-1,10-phenanthroline through the facile Pd-catalyzed coupling of a triphenyltriazine boronic ester with 3-hromo-1,10-phenanthroline. It shows a high Tg of 112℃. The ultraviolet photoelectron spectroscopy measurements reveal a deep HOMO level of -6.5 eV. The LUMO level is derived as -3.0 eV, based on the optical bandgap. The low-temperature solid-state phosphorescent spectrum gives a triplet energy of -2.36eV. n-Doping with 8-hydroxyquinolatolithium （Liq, 1：1） leads to considerably improved electron mobility of 5.2 × 10 -6 -5.8 × 10 -5 cm2 v-1 S-1 at E=（2-5） × 10 5Vcm -1, in contrast with the triarylphosphine oxide- phenantroline molecular conjugate we reported previously. It has been shown that through optimizing the device structure and hence suppressing polaron-exciton annihilation, introducing this single Liq-doped electron-transport layer could offer high-efficiency and stable phosphorescent OLEDs.展开更多
In this work,efficient green electroluminescent（EL）devices with simplified device structure were prepared by doping trivalent terbium complex Tb（PMIP）3into hole block material Tm Py PB.The high triplet energy of T...In this work,efficient green electroluminescent（EL）devices with simplified device structure were prepared by doping trivalent terbium complex Tb（PMIP）3into hole block material Tm Py PB.The high triplet energy of Tm Py PB helps to confine excitons within light-emitting layer,while the electron transport characteristic of Tm Py PB facilitates the balance of carriers on Tb（PMIP）a3molecules.By optimizing the doping concentration of Tb（PMIP）a3and the thickness of each functional layer,highly efficient green EL device with the structure of ITO/Mo Oa3（3 nm）/TAPC（50 nm）/Tb（PMIP）a3（30 wt%）：Tm Py PB（25 nm）/Tm Py PB（60 nm）/Li F（1 nm）/Al（100 nm）displayed pure Tb^3＋ characteristic emission with maximum current efficiency,power efficiency and brightness up to 47.24 cd/A（external quantum efficiency（EQE）of 14.4%）,43.63 lm/W and 1694 cd/m^2,respectively.At certain brightness of 100 cd/m^2,the device still maintained a current efficiency of 19.96 cd/A（EQE=6.1%）.Such a device design strategy helps to improve the EL performances of Tb（PMIP）a3and to simplify device fabrication processes,thus reduce the fabrication cost.展开更多
基金supported by the National Key R&D Program of China(2016YFB0400701)NSFC-Guangdong Joint Program(U1301243)+1 种基金the National Basic Research Program of China(2015CB655000)support of Dongguan Major Special Project(2017215117010)
文摘There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（4,6-diphenyl-l,3,5-triazin-2-yl）phenyl）-1,10-phenanthroline through the facile Pd-catalyzed coupling of a triphenyltriazine boronic ester with 3-hromo-1,10-phenanthroline. It shows a high Tg of 112℃. The ultraviolet photoelectron spectroscopy measurements reveal a deep HOMO level of -6.5 eV. The LUMO level is derived as -3.0 eV, based on the optical bandgap. The low-temperature solid-state phosphorescent spectrum gives a triplet energy of -2.36eV. n-Doping with 8-hydroxyquinolatolithium （Liq, 1：1） leads to considerably improved electron mobility of 5.2 × 10 -6 -5.8 × 10 -5 cm2 v-1 S-1 at E=（2-5） × 10 5Vcm -1, in contrast with the triarylphosphine oxide- phenantroline molecular conjugate we reported previously. It has been shown that through optimizing the device structure and hence suppressing polaron-exciton annihilation, introducing this single Liq-doped electron-transport layer could offer high-efficiency and stable phosphorescent OLEDs.
基金supported by the Research Equipment Development Project of Chinese Academy of Sciences(Grant No.YZ201562)the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.Y72014)+3 种基金the Program of Science and Technology Development Plan of Jilin Province of China(Grant No.20170519006JH)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB20000000)the National Natural Science Foundation of China(Grant Nos.21771172,21521092,21590794,21210001)the National Key Basic Research Program of China(Grant No.2014CB643802)
文摘In this work,efficient green electroluminescent（EL）devices with simplified device structure were prepared by doping trivalent terbium complex Tb（PMIP）3into hole block material Tm Py PB.The high triplet energy of Tm Py PB helps to confine excitons within light-emitting layer,while the electron transport characteristic of Tm Py PB facilitates the balance of carriers on Tb（PMIP）a3molecules.By optimizing the doping concentration of Tb（PMIP）a3and the thickness of each functional layer,highly efficient green EL device with the structure of ITO/Mo Oa3（3 nm）/TAPC（50 nm）/Tb（PMIP）a3（30 wt%）：Tm Py PB（25 nm）/Tm Py PB（60 nm）/Li F（1 nm）/Al（100 nm）displayed pure Tb^3＋ characteristic emission with maximum current efficiency,power efficiency and brightness up to 47.24 cd/A（external quantum efficiency（EQE）of 14.4%）,43.63 lm/W and 1694 cd/m^2,respectively.At certain brightness of 100 cd/m^2,the device still maintained a current efficiency of 19.96 cd/A（EQE=6.1%）.Such a device design strategy helps to improve the EL performances of Tb（PMIP）a3and to simplify device fabrication processes,thus reduce the fabrication cost.
