Research On Electroluminescence Of The Devices Base On CdSe Quantum Dot

Quantum dots is a kind of ideal fluorescent material because of its wide range of excitation spectrum and continuous, narrow and symmetric photoluminescence spectra, emitting light colors can be adjusted, good photochemical stability, high electron mobility. Quantum dots have great application potential in electroluminescent devices. The study of quantum dots and organic polymer composite electroluminescent has important theoretical significance and application value.In this paper, in order to improve the brightness of the quantum devices, we have taken the following two methods:(1) Insert molybdenum oxide (MoO3) layer as the charge generation layer to improve the quantum dot light emitting device; We have prepared the based devices and the two superposed quantum dot devices with inserted molybdenum oxide (MoO3) layer and obtained luminescent of the two sets of thedevices by testing. And further optimize the device structure, modified by the cathode and anode, the luminance quantum dot devices is further improved, and analyzes the internal physical cause which involves.(2) Taking the energy transfer into account, we have inserted the Ir (ppy)3:CBP layer, the Ir (ppy)3is worked as the effective exciton and the energy donor, by adjusting the concentration and the donor and acceptor-distance to the body, so that the quantum dot device luminescence enhancement. We have prepared a group of quantum dot device with the doping concentration from5%to30%, with the doping concentration increases, the Luminescence of the quantum dots first increased then decreased, and at low concentrations was only quantum dot light emitting can be observed, With increasing concentration, Ir (ppy)3also began to glow.The presence of a suitable critical concentration of15%so that the quantum dot light emitting reaches the optimum value. Finally, this paper also studied the electroluminescent process of the red, green, and blue colors of the quantum dot hybrid device. Hybrid device is mixed two kinds of red, green, and blue colors of quantum dots in a1:1ratio, and prepared a structure for the ITO/PEDOT:PSS/QDs/Al devices.By systematically investigating the electroluminescent spectrum, when the voltage increases, we find that the luminance intensity of the control devices continue to grow, while the hybrid QDs devices first increase then decrease, which shows that there is energy transfer in the hybrid QDs devices. And we also got the relationships between the energy transfer efficiency, the critical energy transfer distance, the donor-acceptor distance and the electric.Studying the emitting electronic process of the quantum dot devices and the spectral varies with doping density and operating voltage which can achieve good, stable physical and chemical properties of quantum dots and organic electroluminescent devices composite materials provide important guidance.