Efficient deep-red organic light-emitting diodes （OLEDs） were investigated based on the blend of poly[2- methoxy-5-（2＇-ethyl-hexyloxy）-1,4-phenylene vinylene] （MEH-PPV） with 4,7-bis（5-（7-（9H-carbazol-9-yl）-...Efficient deep-red organic light-emitting diodes （OLEDs） were investigated based on the blend of poly[2- methoxy-5-（2＇-ethyl-hexyloxy）-1,4-phenylene vinylene] （MEH-PPV） with 4,7-bis（5-（7-（9H-carbazol-9-yl）-9,9-dioctyl-9H- fluoren-2-yl）thiophen-2-yl）benzo[c] [1,2,5] thiadiazole （compound 1）. By optimizing the blend ratio, the turn-on voltage of the devices was significantly reduced from 4.9 V to 2.4 V. A highest external quantum efficiency of 2.56% was achieved at a blend ratio of 95：5 （wt） for compound 1： MEH-PPV. The CIE coordinate was measured to be （0.70, 0.30）, with the luminescence peak at around 680 nm. Based on experimental observations the improvement mechanism is described.展开更多
A new thieno-[3,4-b]-pyrazine-cored dendrimer with polyphenyls dendrons （D2TP） was designed and synthesized for application as red emitter in non-doped organic light-emitting diodes （OLEDs）. The bulky dendritic ar...A new thieno-[3,4-b]-pyrazine-cored dendrimer with polyphenyls dendrons （D2TP） was designed and synthesized for application as red emitter in non-doped organic light-emitting diodes （OLEDs）. The bulky dendritic arms enable this molecule to possess significant molecular weight and good solubility in common organic solvents. As a result, D2TP is suitable for solution processing methods such as spin coating to make thin films and devices. In addition, these large dendrons provide site-isolation effect on the planar emissive core to prevent fluorescence quenching or intermolecular interaction. The photophysical and electrochemical properties of D2TP were investigated in its dilute solutions. D2TP was used as non-doped emitter to fabricate OLEDs by spin coating method and saturated red electroluminescence was obtained.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.61036007 and 60937001)Ministry of Science and Technology of the People's Republic of China(Nos.2009CB930604 and 2009CB623604)
文摘Efficient deep-red organic light-emitting diodes （OLEDs） were investigated based on the blend of poly[2- methoxy-5-（2＇-ethyl-hexyloxy）-1,4-phenylene vinylene] （MEH-PPV） with 4,7-bis（5-（7-（9H-carbazol-9-yl）-9,9-dioctyl-9H- fluoren-2-yl）thiophen-2-yl）benzo[c] [1,2,5] thiadiazole （compound 1）. By optimizing the blend ratio, the turn-on voltage of the devices was significantly reduced from 4.9 V to 2.4 V. A highest external quantum efficiency of 2.56% was achieved at a blend ratio of 95：5 （wt） for compound 1： MEH-PPV. The CIE coordinate was measured to be （0.70, 0.30）, with the luminescence peak at around 680 nm. Based on experimental observations the improvement mechanism is described.
基金Project supported by the National Natural Science Foundation of China （Nos. 20704002, 20923006, 21072026）, the Ministry of Education for the New Century Excellent Talents in University （No. NCET-08-0074）, and the Fundamental Research Funds for the Central Universities （No. DUT 10LK 16）.
文摘A new thieno-[3,4-b]-pyrazine-cored dendrimer with polyphenyls dendrons （D2TP） was designed and synthesized for application as red emitter in non-doped organic light-emitting diodes （OLEDs）. The bulky dendritic arms enable this molecule to possess significant molecular weight and good solubility in common organic solvents. As a result, D2TP is suitable for solution processing methods such as spin coating to make thin films and devices. In addition, these large dendrons provide site-isolation effect on the planar emissive core to prevent fluorescence quenching or intermolecular interaction. The photophysical and electrochemical properties of D2TP were investigated in its dilute solutions. D2TP was used as non-doped emitter to fabricate OLEDs by spin coating method and saturated red electroluminescence was obtained.
