The Research On Perovskite Single Crystal Growth And Optoelectronic Devices

As researchers study the photoelectric properties of perovskite,it has become one of the most promising new materials in the fields of photovoltaic power generation,photoelectric detection and light-emitting semiconductor.We have learned a lot about the crystallization of perovskite,including mature synthesis methods and relatively perfect crystal crystallization theory.Nowadays,perovskite polycrystalline films or single crystals are prepared by heating spin coating or solution inversion crystallization,respectively.In contrast,perovskite single crystal has high photoelectric conversion efficiency and better stability.Meanwhile,in order to control the morphology and properties of perovskite single crystal.Prefabricated templates or organic macromolecular skeletons are commonly used to induce their growth.In this paper,different crystallization strategies were adopted to regulate the growth of perovskite single crystals.The main work is as follows:1)In combination with the space-limited perovskite single crystal growth method,under the condition of temperature inversion crystallization,the solute in the perovskite precursor solution was asymmetrically affected by PET flexible substrate and ordinary glass substrate,and the stable and repeatable tower perovskite single crystal with morphology was obtained.2)The response rate of 9.4 A/W and detection rate of 2.1×10¹¹ Jones were obtained by using high quality tower perovskite single crystal to prepare the photodetector with excellent performance.At the same time,combined with the PET flexible substrate,the flexible single crystal device was tested,and the single crystal photodetector which still works stably after bending was obtained.3)The perovskite single crystal heterostructures were grown according to the different loss rates of different components in the mixed solution.A single crystal heterojunction with vertical structure of MA（BA）₂Pb₂Br₇/MAPb Br₃ was obtained.Then the growth of perovskite heterojunction with different solution concentration and solute ratio was further discussed and explored.