Controllable Preparation And Optoelectronic Performance Ofone-dimensional Organometallic Halide Perovskite Materials

The one-dimensional perovskite-type CH₃NH₃PbI₃ nanomaterials have the advantages of large volume-surface area,anisotropic geometrical properties,quantum size effects,etc.,which have potential applications in the field of optoelectronic devices,such as solar cells,light-emitting diodes,photodetectors and etc.However,the size and composition of the CH₃NH₃PbI₃ nanowires are still challenging to control.The relationship between the photoelectric properties and the size and composition of the nanowires is not clear.Therefore,the one-dimensional perovskite-type CH₃NH₃PbI₃ nanomaterials is used by a simple method.It is very necessary to controllably prepare and study the relationship between its photoelectric properties and nanowire size and composition.?1?Pure phase single-crystal perovskite-type CH₃NH₃PbI₃ nanowires were prepared using two-step spin coating method.The effects of different concentration of N,N-dimethylpyrrolidone,methylamine iodine and lead iodide on the morphology and phase of CH₃NH₃PbI₃ nanowires were studied,and the controllable preparation of nanowires was achieved.The optical properties and fluorescence properties of pure phase CH₃NH₃PbI₃nanowires have also been investigated and the relationship between the photoelectric properties and size of CH₃NH₃PbI₃ nanowires prepared under different amounts of lead iodide was further studied.The results showed that the photocurrent increased with the increase of CH₃NH₃PbI₃ nanowires size.?2?Based on the preparation of CH₃NH₃PbI₃ nanowires,a controllable composition of bromine-doped CH₃NH₃Pb(I_1-xBr_x)₃ nanowires were prepared by two-step spin coating method.The effects of bromine content on the morphology,phase and optical properties of CH₃NH₃Pb(I_1-xBr_x)₃ were studied.The results showed that the color of CH₃NH₃Pb(I_1-xBr_x)₃nanowires gradually changed from black to yellow;the band gap of CH₃NH₃Pb(I_1-xBr_x)₃nanowires increased.The stability of photodetector improved as the content of bromine element increased.When the content of bromine in the nanowires was x=0.25,the optical properties of the prepared CH₃NH₃Pb(I_1-xBr_x)₃ nanowires was the most stable.