Modulaition Of Optical Performance Of Perovskite Via Laser Processing Method

All-inorganic metal halide perovskite material（CsPbX₃,X=Cl,Br,I）is a new semiconductor material with excellent optoelectronic properties.The optical properties of inorganic perovskites are closely related to their morphology and composition,so their optical properties can be tuned by changing the material parameters.Optoelectronic device technology based on perovskite materials is currently transitioning from basic research to pre-industrial stage.As the most advanced technology in the 21st century,laser processing technology can be applied to the processing of perovskite materials.Laser processing based on all-inorganic metal halide perovskite materials can easily and quickly enhance and modulate perovskite materials,thereby promoting the development of perovskites in the field of optoelectronic devices.This paper first summarizes the synthesis methods of inorganic perovskites with different morphologies,which lays the foundation for the subsequent processing of perovskites;then introduces the application of different laser processing technologies in the field of perovskites,and analyzes the relationship between laser and matter.interaction.This dissertation carried out related research,the main research results are as follows:（1）The preparation method of inorganic halogen perovskite nanocrystals of different morphologies is introduced.In order to meet the application requirements of different optoelectronic devices,we prepared perovskite nanocrystals of different morphologies with high temperature heat injection method,water and oil interface method,cell crushing method and room temperature solution method,from zero-dimensional to one-dimensional to two-dimensional nanocrystals,and basically characterized their properties.The preparation methods introduced in this chapter are typical methods in the preparation of perovskite nanocrystals,and the morphology and components of perovskite nanocrystals can be adjusted through the adjustment of experimental parameters,we analyzed the advantages and disadvantages of different preparation methods,and discussed the growth kinetics process of perovskite nanocrystals,laying a material foundation for subsequent laser processing of perovskites.（2）The photoluminescence performance of perovskite quantum dots is enhanced by preparing aluminum plasma by laser liquid-phase ablation technology.In inorganic halogen perovskite quantum dots,blue quantum dots have a low quantum yield due to their own more defects,so the enhancement of luminescence for blue quantum dots has always been a key problem.In this work,we used a 1064 nm pulsed laser to laser liquid ablation of aluminum targets in a solvent,and the aluminum nanoparticles dispersed in the solvent had a plasma resonance effect in the deep ultraviolet region,which enabled us to achieve a 1.52-fold enhancement in the luminescence of blue Cs Pb Br_3-xCl_xquantum dots.We discussed the effect of laser experimental parameters on the resonance effect of plasma from experiments and theory,analyzed the interaction between laser and metal,and profoundly studied the effect mechanism of plasma resonance effect on the luminescence of perovskite,which opened up a new development direction for the enhancement of the luminescence of perovskite quantum dots.（3）The light-controlled orientation technology is used to modulate the polarization properties of perovskite light emission and apply it to a new type of liquid crystal display.Light-controlled alignment technology is a method of using polarized ultraviolet light to make liquid crystal molecules orderly arranged.In this work,light-controlled alignment technology is used to align liquid crystal molecules and perovskite nanowires to improve the perovskite composite film.Polarized luminescence properties and we analyzed its orientation principle.We have carried out a series of characterizations on the polarized luminescence properties of the Cs Pb Br₃ nanowire-liquid crystal composite film.The anisotropy parameter of the film’s luminescence reaches 0.44,which has a very good polarization.Further,we built an imaging demonstration optical path to test its polarized luminescence.an intuitive demonstration.In this work,we developed the micro-light-controlled orientation technology for the first time,realized the application of micro-domain polarization patterning,and promoted the development of new liquid crystal display technology.（4）Using laser direct writing technology to print silver interdigital electrodes and apply them to perovskite photodetectors.Two-dimensional perovskite nanosheets show great potential on photodetectors because of their high stability and large light absorption coefficient,and this paper successfully prepares perovskite nanosheet detectors using laser direct writing technology.In this work,the method of preparing silver electrodes by laser direct writing technology is introduced,and the influence of laser experimental parameters（laser spot size,laser power,scanning speed）on electrode morphology and conductivity is discussed.In order to better analyze the experimental results,we proposed and defined the concept of"dose"in laser direct writing technology,and the introduction of"dose"definition helped us to better quantitatively understand the process of laser direct writing printing silver electrodes,and also helped us better adjust the parameters to prepare the optimal electrode.The minimum Rs thin layer resistance of the silver electrode we prepared was 1.3Ω/sq,which was applied to the perovskite nanosheet detector,and the detector showed good detection performance,which laid the foundation for the future development of fully printed perovskite optoelectronic devices.