| 1 | An organic light-emitting devices of highly efficient white phosphor using an electron/exciton blocker显示文摘Highly efficient white phosphorescent organic light-emitting devices (WOLEDs) was fabricated using an electron/exciton blocker. The device structure is ITO/2T-NATA(25 nm)/ NPBX(25-dnm)/CBP:5%Ir(ppy)3:0.5%Rubrene(8 nm)/NPBX(dnm)/ DPVBi(30 nm)/TPBi(20 nm)/Alq(10nm)/LiF(1nm)/Al, in which N,N '-bis- (1-naphthyl)- N,N '-diphenyl -1, 1 '- bi- phenyl-4,4 '-diamine (NPBX) functions as a hole transport layer and electron/exciton blocker, 4,4,N,N '- dicarbazolebiphenyl (CBP) is host, 4,4'-bis(2,2 -diphenyl vinyl)-1,1 '-biphenyl (DPVBi) is blue fluorescent dye, 5,6,11, 12,-tetraphenylnaphthacene (rubrene) is fluorescent dye, factris (2-phenylpyridine) iridium (Ir(ppy)3) is phosphorescent sensitizer and tris(8-hydroxyquinoline) aluminum (Alq3) is an electron transport layer. The WOLEDs have obtained white light emission by adjusting the thickness of NPBX , when the concentration of Ir(ppy)3 is 5-wt% and rubrene is 0.5-wt%, respectively, the thickness of the doped emissive layer is 8 nm, the WOLEDs show a maximum luminous efficiency is 11.2 cd/ A with d of 10 nm at 7 V and a maximum luminance of 28170 cd/m2 at 17 V, the CIE coordinates is (0.37.0.42), which is in white region. | JIANG Wen-long , DING Gui-ying, WANG Jin,WANG Jing , WANG Li-zhong , CHANG Xi,HAN Qiang , WANG Hong-mei , and ZHAO Xiao-hong College of information Technology , Jilin Normal University, Siping 136000,China | 2008 | Optoelectronics Letters2008,4,1: | 7 |
| 4 | Tuning Exciton Recombination Pathways in Inorganic Bismuth-Based Perovskite for Broadband Emission显示文摘Single-component emitters with broadband emission are attractive but challenging for illumination and display applications.The two-dimensional organic-inorganic hybrid perovskites have exhibited outstanding broad emission property due to low electronic dimensionality and strong exciton-phonon coupling.However,few layered all-inorganic lead-free perovskites with broadband emission have been explored,and the explicit mechanism of exciton recombination in them also needs in-depth understanding.Herein,the inorganic bismuth-based perovskite Cs3Bi2Br9 achieves the stable broadband emission under ambient temperature and pressure by tuning the exciton recombination pathways via antimony(Sb)doping,and the photoluminescence quantum yield(PLQY)realizes an enhancement from 2.9%to 15.9%.The photoluminescence excitation(PLE)spectra indicate that the doped Sb introduces newly extrinsic self-trapped states.The incorporation of Sb promotes the transfer of free excitons(FEs)to extrinsic self-trapped excitons(STEs)observed from Sb content-dependent steady-state PL spectra and,meanwhile,reduces the nonradiative recombination of the generated extrinsic STEs,which are primarily responsible for the remarkably enhanced broad emission.Furthermore,femtosecond transient absorption results elucidate a clear exciton dynamics,in which the transition from FEs to STEs might arise through the gradient energy levels,and finally extrinsic STEs at various energy states contribute to the broadband emission. | Ming Shi Bin Yang Siping Liu Ruiling Zhang Keli Han Can Li Rengui Li | 2022 | Energy Material Advances2022,,1: | 0 |