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Since the first organic double heterostructure devices since the eighties of the last century, the United States Kodak Deng Qingyun, optoelectronic devices of small organic molecules, such as the organic thin-film solar cell (Organic Solar Cells OSCs), electroluminescent devices (Organic Light- Emitting Diodes, OLEDs), organic thin-film transistor (Organic Thin Film Transistor, OTFT) and organic lasers (Organic Laser), by research institutions and industry has broad application prospects widespread concern. Currently restricted due to the low efficiency of the device working mechanism is imperfect, the rapid development of organic optoelectronic devices. Therefore, the exciton confinement method to improve the device efficiency goals, the specific content of the study are as follows: 1. 2 - (4-biphenylyl)-5-phenyl-1, 3, 4-oxadiazole (PBD) as exciton blocking layer preparation the OSCs device, examines the PBD exciton blocking layer to the barrier layer thickness on the performance of the devices of the device the absorption spectra of different PBD exciton obtained PBD exciton blocking layer thickness of 5 nm, device optimal efficiency. Because exciton blocking layer, the device of the diffusion of excitons to the cathode has been suppressed. Therefore, the excitons in the probability of separation of the donor receptor interface increases, the increase in the number of effective separation of excitons, so that the device efficiency is improved. 2 mCP (N, N'-dicarbazolyl-3, 5-benzene) doped (t-bt) 2 Ir (acac) [bis [2 - (4-tertbutylphenyl) benzothiazolato-N C 2 ] iridium (acetylacetonate) prepared device structure of ITO / NPB (40 nm) / mCP: (t-bt) 2 Ir (acac) ( 8% D nm) / MCP (30-d nm) / TPBI (30 nm) / Mg: Ag (200 nm) of the device, wherein d = 5, 10, 15, 20, 25, 30 nm. Analysis found that the photoluminescence spectrum (Electroluminescence, EL) device electrically two light emitting peak of the device, respectively from the mCP and (t-BT) the 2 Ir (acac) of the emission peak. Two emission peak intensity with the device doped layer thickness variation trend analysis results show that when the thickness of the doped layer of the device is about 15 nm, two emission peak intensity of the device appears obvious mutation, this is because when d = 15 nm, more from the non-doped layer MCP triplet exciton diffusion into the doped layer, resulting in the mCP and (t-BT) the 2 Ir (acac) emission intensity mutation. The analysis of the device using a conventional steady-state exciton diffusion equation, to obtain a three-wire mCP exciton diffusion length of 16 ± 1nm. 3, respectively, to the blue phosphorescent dye BIS [(4,6-diflourophenyl)-pyridinato-N, C 2 )] (picolinato) the Iridium (III) (FIrpic) and a yellow phosphor dye (t -bt) the 2 Ir (acac) for ultra-thin layer of light-emitting layer, the spacer layer prepared mCP as white devices, dual phosphorescent ultrathin layer on the device performance. Device to obtain a stable white light emission, the CIE coordinates of the current efficiency of 11.08 cd / A, the energy efficiency of 6.21 lm / W, the device consistent optimal white area, and the offset is less. The results show that the ultrathin layer of the excitons in the device limiting effect significantly, resulting in a very stable white light emitting device. In summary, this thesis exciton confinement effect on the performance of an organic photovoltaic device, the performance optimization of the organic thin film solar cell and white stable organic electroluminescent device, proposed a novel analytical organic material exciton the diffusion length, i.e. does not change under the premise of the thickness of the light emitting layer, changing the thickness of the doped layer of the device, through device electrically induced Trend analysis of different emission peak intensity in the emission spectrum, can be drawn to the exciton diffusion length. Exciton confinement role analysis results show that the exciton blocking layer and phosphorescent ultrathin layer can effectively play the role of the exciton confinement, to improve the performance of organic optoelectronic devices.
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