二维钙钛矿单晶材料制备及X射线响应性能研究OA

The organic-inorganic hybrid two-dimensional perovskites,with their special quantum well structures,have attracted increasing attention in the field of optoelectronic semiconductors.Exploring the differences in optoelectronic properties of different quantum well structures is helpful for promoting the application of two-dimensional perovskite materials.Typical phenylethylamine(PEA)and butylamine(BA)are selected as the spacer layer cations.Centimeter-sized two-dimensional PEA2PbBr4,BA2PbBr4,and BA2MAPb2Br₇ perovskite single crystals are prepared through a cooling crystallization process combined with a composition regulation strategy.The crystal morphology and structure are analyzed by means of characterization techniques such as scanning electron microscopy(SEM)and X-ray diffraction(XRD).The photophysical properties of the three crystals are compared by ultraviolet-visible absorption spectroscopy and fluorescence spectroscopy.X-ray photoelectric response devices are prepared by evaporating symmetric electrodes to explore the optoelectronic properties of the two-dimensional BA2PbBr4 and BA2MAPb2Br₇perovskite single crystals.In view of the anisotropic differences of two-dimensional crystals,devices with vertical and horizontal structures are prepared respectively.For the device with a horizontal structure based on BA2PbBr4,when the X-ray irradiation intensity is 80.73 μGy·s-1,its maximum sensitivity is 192.5 μC·Gy-1·cm-2,and the maximum sensitivity of the device based on BA2MAPb2Br₇is 194.6 μC·Gy-1·cm-2.Due to the influence of the quantum well confinement,the response sensitivity of the vertical structure is relatively low,having sensitivities of 88 μC·Gy-1·cm-2 and 74 μC·Gy-1·cm-2 respectively.