| Metal halide luminescent materials have abundant crystal structures and excellent photoelectric properties.Their luminescent properties can be modified via constructing different crystal structures.Some materials also present significant quantum size effects and their luminescent properties can be changed via adjusting the crystal size.Metal halide luminescent materials are considered to be highly likely to replace expensive rare earth or noble metal luminescent materials.Among them,lead halide perovskite and copper（Ⅰ）based organic-inorganic hybrid materials have the advantages of tunable spectra,high photoluminescence quantum yield,large stokes shift and solvable process,which have attracted a broad research interest.However,it is still challenges to develop high-efficient,low-cost,high-quality and green synthesis method of lead halide perovskite and copper（Ⅰ）based organic-inorganic hybrid materials and expand their applications.This thesis focuses on surface coating,size control,green synthesis,structural and optical design and applications of metal halide luminescent materials.It has carried out research on the preparation,property regulation and applications of organic metal halide luminescent materials.The specific research work includes the following four aspects:（1）MAPb Br3@Pb Br（OH）（MA:CH3NH3）nanocrystals were synthesized rapidly,efficiently and environmentally friendly via the aqueous grinding process in the presence of 2-methyl-imidazole（2-MIM）and oleylamime（OAm）,and highly stalbe waterborne luminescent inks based on MAPb Br3@Pb Br（OH）nanocrystals were developed.2-MIM triggers the formation of Pb Br（OH）matrix,which encapsulates and protects the perovskite effectively,while OAm acts as a size-control ligand to control the size of MAPb Br3@Pb Br OH particles in the nanoscale range.Benefit from good dispersion in waterborne polymers of the prepared nanocrystals,and the environmentally friendly waterborne luminescent inks were successfully prepared.The luminescent films prepared by scratch coating exhibit excellent stability to the environment under thermal and light irradiation and resistance to organic solvents.We also develope waterborne anti-counterfeit luminescent inks and the fluorescent anti-counterfeit patterns were obtained through screen printing.（2）Cu I hybrid micron phosphors with tunable luminescence were prepared via the aqueous PVP micelle-assisted assembly route and their applications were explored.Seven Cu I hybrid micron phosphors with different sizes,morphologies and emission were successfully synthesized by PVP assisted modulation and the reaction of different organic ligands with Cu I using water as the solvent.It was found that PVP can effectively limit the crystal size growth and control the formation of different crystal phases.Among them,Cu I-pyridine hybrid micron phosphors can be obtained via the reaction of Cu I with various pyridines.Whereas,micron phosphors based on bidentate ligands including 2-propylpyrazine,5-bromopyrimidine or 4,4’-bipyridine need to be prepared via ligand exchange reaction.The micron phosphors can be dispersed in waterborne polymers to form homogeneous luminescent composites.The luminescent composites are easy to fabricate anti-counterfeiting patterns,monochromatic or multichromatic luminescent films as color convertor for display backlight.In addition,the white LED can be directly realized via optimizing the mixing ratio of blue and orange phosphors.（3）The highly stable copper（Ⅰ）halide phosphors encapsulated in fumed silica were synthesized via aqueous mechanochemical process.The copper（Ⅰ）halide phosphors encapsulated in fumed silica were rapidly prepared by mechanical grinding with the copper（Ⅰ）halides,sodium halides,fumed silica and 18-crown-6 were mixed in a certain ratio in the presence of small amounts of water.By using different precursors,we obtain blue,green and orange emission copper（Ⅰ）halide phosphors with high photoluminescence quantum yields.Further,it was confirmed by crystal growth and crystal structure characterization that the green emission is owing to the formation of the well-known 0D-（18-crown-6）2Na2（H2O）3Cu4I6,while the blue and orange emission are ascribed to the formation of the novel 1D-（18-crown-6）2Na2（H2O）3Cu2Cl4 and 0D-（18-crown-6）2Na2（H2O）3Cu4Br6 crystal structures,respectively.We demonstrate that waterborne luminescent inks can be directly prepared from those phosphors via blending them with various waterborne polymers.Interestingly,the combination of orange,green and blue colours can lead to various spectrum,which obtains multiple anti-counterfeiting functions and greatly enhances the fluorescent anti-counterfeiting ability.Further,such phosphors can also be embedded into polystyrene resin to form homogenous luminescent composites,which can be used to prepare free-standing luminescent films and fabricate LEDs with tunable emissions.（4）The luminescence properties of copper（Ⅰ）halide hybrid materials can be effectively changed through regulating their crystal construction.In order to understand the effects of halogen,cavity size of crown ether and alkali metals on the optical properties of crown-ether copper（Ⅰ）halide complexes,we carry out the synthesis of crown-ether copper（Ⅰ）halide complexes via a mechanical grinding method to find that the changing alkali metal ions,halogens and crown ethers can effectively regulate the luminescence properties of crown-ether copper（Ⅰ）halide complexes.Further,crown-ether copper（Ⅰ）halide crystals were growth and their crystal structures were characterized and 14 new structures were achieved.Crown-ether alkali metal cations combined with copper（Ⅰ）halide anion clusters including linear[Cu X2]-,rhombic[Cu2X4]2-and disordered[Cu4X6]2-（X=I,Br,Cl）to form various crystal structures.The crystals have different optical properties with the diverse excitation characteristics,including extremely narrow deep ultraviolet excitation spectra（200-300 nm）,wide excitation spectra（200-450 nm）and ultra-wide excitation bands（300-500 nm）.Their emission spectra range from 470 nm blue to 661 nm red. |
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