Preparation,Doping And Photoelectric Devices Of Inorganic Perovskite Cspbbr₃ Quantum Dots

In recent years,perovskite quantum dots?PeQDs?have become one of the most important materials in the field of optoelectronic due to their advantages such as tunable band gap,high carrier transfer rate,and high photoluminescence quantum yields?PLQYs?.PeQDs have been wildly used in solar cells,light emitting diodes?LEDs?and photodetectors.Light emitting devices based on CsPbBr₃ PeQDs have received high attention from researchers because of the high color purity.This paper has studied the effects of synthesis conditions on the characteristics of the CsPbBr₃ PeQDs by varying the synthesis temperature and reaction time and obtained the perovskite quantum dots with the high photoluminescence?PL?intensity.This work prepared a perovskite quantum dot light-emitting diodes?QLEDs?with TiO₂ film served as the electron transport layer.TiO₂,as a natural N-type conductive material,has been widely used in the preparation of perovskite solar cells.However,the TiO₂ films prepared by the solution spin-coating method usually require a high temperature of hundreds of degrees Celsius,which limits its choice of substrate and its application in optoelectronic devices.In this paper,TiO₂ thin film was prepared at room temperature by magnetron sputtering and successfully applied to perovskite QLEDs.In order to prepare a smooth and uniform TiO₂ film and reduce the density of defect states at the interface between TiO₂ and PeQDs films,this work has studied the crystallinity,surface roughness and optical characteristics of TiO₂ film prepared for different sputtering powers and obtained the optimal precess parameters.The external quantum efficiency of the final prepared perovskite quantum dot LED is 1.53%,and the luminance is 61 cd/m².Besides,the main detection range of perovskite-based photodetectors is in the ultraviolet to visible light band,while there is less research on perovskite infrared photodetectors.In this paper,the CsPbBr₃ QDs have response to the infrared light?⁹80nm?by co-doping rare earth ions Yb³⁺and Er³⁺,and rare earth doped perovskite QDs infrared photodetectors have been prepared.Then,the performance of the infrared photodetector was greatly improved by introducing polymethyl methacrylate photonic crystals?PMMA OPCs?which has a photon stop band matched with the emission peak of the CsPbBr₃ QDs.The designed photodetector achieves a response time of 19?s,a detection rate of 1.27×10¹¹ Jones,and a responsivity of 0.46 A/W.