Controlled Synthesis,Ligand Exchange And Application Of All-inorganic Perovskite Nanocrystals

In recent years,all-inorganic perovskite nanocrystals CsPbX₃（X=Cl,Br,I）have become attractive due to their excellent properties,such as high quantum yield,relatively narrow full width at half maximum,and tunable emission wavelength,etc.There are many studies on synthesis,stability improvement and application.In this paper,we explore the synthesis,ligand exchange and application of CsPbX₃ nanocrystals by combining with AFM technology,fluorescence microscopy technology and 3D printing technology.The details of my research work are as followed:（1）In this paper,CsPbX₃ nanorods with aspect ratios around 2-4 were synthesized by the phase transformation method,and their morphology and optical properties were explored.The results show that the nanorods are about 40nm in length and about 20nm in width and their distribution is uniform;luminescence of the nanorods can cover the whole visible light region which means they possess excellent optical performance.To our knowledge,it is the first the short CsPbX₃ nanorods were reported.（2）We combined the AFM self-assembly technology and the fluorescence microscope to develop a ligand exchange detection method—a point-to-point method to detect the effect of the ligand on the fluorescence intensity change of the quantum dots.We quantified three important experimental parameters:self-assembled charge surface potential,CsPbBr3 quantum dot concentration and organic ligand concentration,to provide a high-throughput test method for studying the effect of CsPbBr3 surface ligand effects,regulation mechanism and influence on optical performance.（3）In terms of application,CsPbX₃ nanocrystals and various rubbers（PDMS rubber,Dow Corning Se1700 rubber,etc.）were mixed and printed into composite flexible waterproof luminescent materials by printing technology.The flexible film can be bent arbitrarily.After being placed in the air for more than 72 hours,95%of the luminescence can still be maintained,the luminescence effect can be maintained even after being immersed in acid,alkali and water for a long time.