PPV-based copolymers with cyano group in the main chain have been synthesized by Wittig-type polycondensation of alkoxy-substituted dialdehydes and 4,4’-bis(cyanomethyl)-substituted diphenyl ether: [―C6H4―O―C6H4―...PPV-based copolymers with cyano group in the main chain have been synthesized by Wittig-type polycondensation of alkoxy-substituted dialdehydes and 4,4’-bis(cyanomethyl)-substituted diphenyl ether: [―C6H4―O―C6H4―C(CN)(CH―C6H2(OR)2―C(C(CN)―]n (POPPV). The copolymers are highly soluble in common solvents and their super highly transparent homogeneous thin films can be formed by spin coating directly without heat treatment. The chemical structures are determined by NMR and IR spectroscopys and evaluated using photoluminescence, gel-permeation chromatography (GPC) and DSC (or TGA) methods. The incorporation of ether group into the PPV backbone has an interruption of the main-chain conjugation, that results in the blue-shift of electroluminescence spectra and enhancement the solubility.展开更多
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
Naphthalimide derivatives, N-ethyl-4-acetylamino-l,8-naphthalimide (EAAN) and polymer with N-propyl-4-acetylamino-1,8-naphthalimide (PAAN) side-chain (P-PAAN) were successfully synthesized. Electroluminescent devices ...Naphthalimide derivatives, N-ethyl-4-acetylamino-l,8-naphthalimide (EAAN) and polymer with N-propyl-4-acetylamino-1,8-naphthalimide (PAAN) side-chain (P-PAAN) were successfully synthesized. Electroluminescent devices of ITO/PVK(120nm)/EAAN(50nm)/Al(150nm) (I) and ITO/PVK+ P-PhAN(10:1) (50nm)/Al( 150nm) (II) constructed with EAAN and P-PAAN as the emitting layer were investigated, whereas the single-layer devices of ITO/EAAN or P-PAAN(50nm)/Al(150nm) (III) were not observed to have any e-mission light. The emission results revealed that the exaction recombination formed by positive and negative charge carriers injected from electrodes of devices I and II was much more balanced than that of devices III, which implied that naphthalimide derivatives are a new type of electron-transporting materials with high performance. The electron-transporting properties of naphthalimide derivatives were also elucidated by investigation of the electroluminescent behaviors from both devices of ITO/PPV (80nm)/Al and ITO/PPV (80nm)/EAAN (20)nm)/Al hch fabricated with EAAN as the electron-transporting layer.展开更多
基金Natural Science Foundation of Tianjin(No.003602511).
文摘PPV-based copolymers with cyano group in the main chain have been synthesized by Wittig-type polycondensation of alkoxy-substituted dialdehydes and 4,4’-bis(cyanomethyl)-substituted diphenyl ether: [―C6H4―O―C6H4―C(CN)(CH―C6H2(OR)2―C(C(CN)―]n (POPPV). The copolymers are highly soluble in common solvents and their super highly transparent homogeneous thin films can be formed by spin coating directly without heat treatment. The chemical structures are determined by NMR and IR spectroscopys and evaluated using photoluminescence, gel-permeation chromatography (GPC) and DSC (or TGA) methods. The incorporation of ether group into the PPV backbone has an interruption of the main-chain conjugation, that results in the blue-shift of electroluminescence spectra and enhancement the solubility.
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.
文摘Naphthalimide derivatives, N-ethyl-4-acetylamino-l,8-naphthalimide (EAAN) and polymer with N-propyl-4-acetylamino-1,8-naphthalimide (PAAN) side-chain (P-PAAN) were successfully synthesized. Electroluminescent devices of ITO/PVK(120nm)/EAAN(50nm)/Al(150nm) (I) and ITO/PVK+ P-PhAN(10:1) (50nm)/Al( 150nm) (II) constructed with EAAN and P-PAAN as the emitting layer were investigated, whereas the single-layer devices of ITO/EAAN or P-PAAN(50nm)/Al(150nm) (III) were not observed to have any e-mission light. The emission results revealed that the exaction recombination formed by positive and negative charge carriers injected from electrodes of devices I and II was much more balanced than that of devices III, which implied that naphthalimide derivatives are a new type of electron-transporting materials with high performance. The electron-transporting properties of naphthalimide derivatives were also elucidated by investigation of the electroluminescent behaviors from both devices of ITO/PPV (80nm)/Al and ITO/PPV (80nm)/EAAN (20)nm)/Al hch fabricated with EAAN as the electron-transporting layer.
