Research On Luminescent Properties Of Mn²⁺/Bi³⁺ Doped All-Inorganic Lead-free Perovskite

The all-inorganic halide non-lead perovskite solves the lead toxicity problem of the lead-containing perovskite,and has the advantages of cheap and easy-to-obtain raw materials,simple synthesis process,and high luminous efficiency.It has become a perfect candidate for the next generation of practical lighting display materials.one.However,the all-inorganic halide non-lead perovskite has a single fluorescence and the disadvantages of difficult adjustment limit its application in more fields.As a classic method,metal ion doping brings more unique optical and electrical properties to perovskites,laying a foundation for the application of perovskites in new fields.In this thesis,the following researches are carried out in response to the above problems:(1)Using Cs₂Ag_0.6Na_0.4InCl₆ as the carrier,Mn²⁺is doped by high-temperature hydrothermal method to obtain a lead-free double perovskite with switchable fluorescence.Due to the effective energy transfer between the matrix and Mn²⁺,the material can operate at 365 and 254nm,Showing bright warm white light and red light emission,respectively,as the representatives of"0"and"1",all information can be re-encoded into computer language,which shows that it has a huge application prospect in the field of visible light communication;At the same time,the material has good self-repairing properties of crystal phase in the acidic aqueous solution rich in Cl^-,showing recoverable fluorescence,combined with switchable fluorescence,showing the application of this material in information storage,anti-counterfeiting and other fields prospect.(2)Using Cs₂InCl₅.H₂O as the carrier,through high temperature hydrothermal co-doping of Bi³⁺,Mn²⁺,a lead-free perovskite with excitation-dependent tunable fluorescence is obtained.Thanks to the effective energy transfer between the matrix and Mn²⁺,Bi³⁺,this material The excitation wavelength changes from 290-320 nm,showing tunable fluorescence from blue to red.By adjusting the doping ratio of Mn²⁺and Bi³⁺,the most suitable doping concentration is finally confirmed,and get white fluorescence close to standard white light(0.33,0.33).