An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply...An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply red electroluminescence with a maximum luminance of 56.8 cd/m 2 at 48 V was achieved.展开更多
A novel iridium-complex,(BPPBI) 2 Ir(2-TFDBC)[BPPBI=2-(biphenyl-4-yl)-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-(9-ethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and c...A novel iridium-complex,(BPPBI) 2 Ir(2-TFDBC)[BPPBI=2-(biphenyl-4-yl)-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-(9-ethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and component were confirmed by 1 H NMR and element analysis,respectively.UV-Vis absorption and photoluminescent(PL) spectra of(BPPBI) 2 Ir(2-TFDBC) in dichloromethane were investigated.The Ir-complex exhibited a long wavelength excitation of 470 nm,i.e.,low-energy excitation.So,it is a promising candidate for phosphorescent probe and PL material.(BPPBI) 2 Ir(2-TFDBC)-based electroluminescent devices,ITO/MoO 3(10 nm)/NPB(80 nm)/CBP:x(BPPBI) 2 Ir(2-TFDBC)(20 nm)/TPBi(45 nm)/LiF/Al,were fabricated,where x(%) was of 4% or 8% doping concentration(mass fraction);ITO=indium tin oxides;NBP=N,N'-bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1'-biphenyl)4,4'-diamine,CBP=4,4'-bis(N-carbazolyl)-1,1'-biphenyl,TPBi=1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene.The devices showed a red emission of 620 nm.The maximum current efficiency and brightness were 1.7 cd/A and 4063 cd/m 2 for a device of 8%(mass fraction) doping level,respectively.The moderate luminous efficiency was due to the inadequate energy transfer from the host material to the vip material.展开更多
A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa...A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa)2-xEux(MoO4)3 phosphors had an SrMoO4 structure. The properties of these resulting phosphors have also been characterized by using photoluminescence (PL) spectra. The PL results indicate that all of the (SrNa)2-xEux(MoO4)3 phosphors exhibit intense red emissions under 275, 395, and 465-nm excitation. The two strongest lines at 395 and 465 nm in the excitation spectra of these phosphors match well with the two popular emissions from near-UV and blue GaN-based light-emitting diodes. Some process parameters for Eu3+ concentration, (C6H8O7)·H2O concentration, and solution pH value were also investigated. For (SrNa)2-xEux(MoO4)3 phosphors, there are two maximum emission intensities appearing with x = 0.6 and x = 1.4, respectively. When the molar ratio of citric acid is equal to that of metal cations and the solution pH is almost 4, (SrNa)2-xEux(MoO4)3 shows the strongest emission intensity compared to those under other conditions.展开更多
A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that ...A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that the zeta-potential of PCD-MCH was 32.8 to16.7 mV at pH 3.0-10.5.The maximum X-3B adsorption capacity of PCD-MCH was2792.3 mg/g.The adsorption kinetics could be well-described by the Weber-Morris model and the homogeneous surface diffusion model(HSDM).Diffusion stages corresponding to surface or film diffusion,intra-particle or wide mesopore diffusion,and narrow mesopore/micropore diffusion occurred at 0-120,120-480 and 480-1200 min,respectively.The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics.At the initial X-3B concentration of 600 mg/L,the diffusion coefficient(Ds) and external mass transfer coefficient in the liquid phase(kF) were 3x10^-11 cm^2/min and 4.68 x 10^-6 cm/min,respectively.X-3B approaching the center of PCD-MCH particles could be observed at 360 min.At the end of the third diffusion stage,the Cp at q/qe=0 was 45.20 mg/L,which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles.At pH 3.0-10.0,PCD-MCH showed stable X-3B adsorption capacities.After five regeneration-reuse cycles,the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g.The corresponding adsorption mechanism was identified as involving electrostatic interactions,cyclodextrin cavities and hydrogen bonds,of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes.展开更多
文摘An Electroluminescent device with PVK film doped with Eu(TTA) 3 Phen and PBD was fabricated. The device structure of glass substrate/indium tin oxide/PPV/PVK∶ Eu(TTA) 3 Phen∶PBD/Alq 3/Al was employed. A sharply red electroluminescence with a maximum luminance of 56.8 cd/m 2 at 48 V was achieved.
基金Supported by the Natural Science Foundation of Guangdong Province,China(No.10152404801000017)
文摘A novel iridium-complex,(BPPBI) 2 Ir(2-TFDBC)[BPPBI=2-(biphenyl-4-yl)-1-phenyl-1H-benzo[d]imidazole,2-TFDBC=1-(9-ethyl-9H-carbazol-2-yl)-4,4,4-trifluorobutane-1,3-dione],was synthesized,and its structure and component were confirmed by 1 H NMR and element analysis,respectively.UV-Vis absorption and photoluminescent(PL) spectra of(BPPBI) 2 Ir(2-TFDBC) in dichloromethane were investigated.The Ir-complex exhibited a long wavelength excitation of 470 nm,i.e.,low-energy excitation.So,it is a promising candidate for phosphorescent probe and PL material.(BPPBI) 2 Ir(2-TFDBC)-based electroluminescent devices,ITO/MoO 3(10 nm)/NPB(80 nm)/CBP:x(BPPBI) 2 Ir(2-TFDBC)(20 nm)/TPBi(45 nm)/LiF/Al,were fabricated,where x(%) was of 4% or 8% doping concentration(mass fraction);ITO=indium tin oxides;NBP=N,N'-bis-(1-naphthalenyl)-N,N'-bis-phenyl-(1,1'-biphenyl)4,4'-diamine,CBP=4,4'-bis(N-carbazolyl)-1,1'-biphenyl,TPBi=1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene.The devices showed a red emission of 620 nm.The maximum current efficiency and brightness were 1.7 cd/A and 4063 cd/m 2 for a device of 8%(mass fraction) doping level,respectively.The moderate luminous efficiency was due to the inadequate energy transfer from the host material to the vip material.
文摘A series of (SrNa)2-xEux(MoO4)3 red phosphors have been synthesized by using the sol-gel method. X-ray diffraction, used to characterize the crystallization process of the phosphor precursors, indicates that the (SrNa)2-xEux(MoO4)3 phosphors had an SrMoO4 structure. The properties of these resulting phosphors have also been characterized by using photoluminescence (PL) spectra. The PL results indicate that all of the (SrNa)2-xEux(MoO4)3 phosphors exhibit intense red emissions under 275, 395, and 465-nm excitation. The two strongest lines at 395 and 465 nm in the excitation spectra of these phosphors match well with the two popular emissions from near-UV and blue GaN-based light-emitting diodes. Some process parameters for Eu3+ concentration, (C6H8O7)·H2O concentration, and solution pH value were also investigated. For (SrNa)2-xEux(MoO4)3 phosphors, there are two maximum emission intensities appearing with x = 0.6 and x = 1.4, respectively. When the molar ratio of citric acid is equal to that of metal cations and the solution pH is almost 4, (SrNa)2-xEux(MoO4)3 shows the strongest emission intensity compared to those under other conditions.
基金supported by the National Key Research and Development Program of China (No.2017YFC0505303)the National Natural Science Foundation of China (Nos.51478041 and 51678053).
文摘A novel polycyclodextrin-modified magnetic cationic hydrogel(PCD-MCH) was developed and its performance,kinetics and mechanism for the removal of reactive brilliant red X-3B(X-3B) were studied.The results showed that the zeta-potential of PCD-MCH was 32.8 to16.7 mV at pH 3.0-10.5.The maximum X-3B adsorption capacity of PCD-MCH was2792.3 mg/g.The adsorption kinetics could be well-described by the Weber-Morris model and the homogeneous surface diffusion model(HSDM).Diffusion stages corresponding to surface or film diffusion,intra-particle or wide mesopore diffusion,and narrow mesopore/micropore diffusion occurred at 0-120,120-480 and 480-1200 min,respectively.The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics.At the initial X-3B concentration of 600 mg/L,the diffusion coefficient(Ds) and external mass transfer coefficient in the liquid phase(kF) were 3x10^-11 cm^2/min and 4.68 x 10^-6 cm/min,respectively.X-3B approaching the center of PCD-MCH particles could be observed at 360 min.At the end of the third diffusion stage,the Cp at q/qe=0 was 45.20 mg/L,which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles.At pH 3.0-10.0,PCD-MCH showed stable X-3B adsorption capacities.After five regeneration-reuse cycles,the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g.The corresponding adsorption mechanism was identified as involving electrostatic interactions,cyclodextrin cavities and hydrogen bonds,of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes.