Study on temperature characteristics of organic light-emitting diodes based on tris-（8-hydroxylquinoline）-aluminum

Both single-layer and double-layer organic light-emitting devices based on tris-（8-hydroxylquino- line）-aluminum （AIq3） as emitter are fabricated by thermal vacuum deposition. The electroluminescent characteristica of these devices at various temperatures are measured, and the temperature characteristics of device performance are studied. The effect of temperature on device current conduction regime is analyzed in detail. The results show that the current-voltage （I-V） characteristics of devices are in good agreement with the theoretical prediction of trapped charge limited current （TCLC）. In addition, both the charge carrier mobility and charge carrier concentration in the organic layer increase with the rise of temperature, which results in the monotonous increase of AIq3 device current. The current conduction mechanisms of two devices at different temperatures are identical, but the exponent m in current-voltage equation changes randomly with temperature. The device luminance increases slightly and the efficiency decreases monotonously due to the aging of AIq3 luminescent properties caused by high temperature. A tiny blue shift can be observed in the electroluminescent （EL） spectra as the temperature increases, and the reduction of device monochromaticity is caused by the intrinsic characteristics of organic semiconductor energy levels.     

CH3 NH3 PbBr3钙钛矿纳米晶的室温合成及发光性能研究

有机-无机杂化钙钛矿材料因光吸收系数大、带隙直接且可调、载流子迁移率高、载流子扩散长度长等优势在光电器件领域显现巨大的应用前景.采用低温合成工艺,实现光学性能调控,对于扩展其应用具有重要研究价值.本文开发了一种室温下合成CH3 NH3 PbBr3纳米晶的简便方法,研究了反应时间对钙钛矿纳米晶的晶体结构和发光性能的影响....