Dynamically Tuning Rare Earth Complexes:Design,Synthesis And Application In Optical Information Printing

Paper plays a very important role in information and knowledge transfer.Conventional inkjet printing has some problems,such as high cost and difficult reutilization.Nowadays,more and more optical information printing technologies have been investigated to solve these problems.Rare earth elements have the advantages of high quantum efficiency,long luminescence lifetime and high color purity.By utilizing the antenna effect and the weak coordination interaction between ligand and rare earth center,the photophysical property regulation of rare earth can be effectively achieved.In this thesis,new rare earth complexes have been developed.Taking advantage of water-induced dynamic coordination,the new optical information printing technologies have been successfully investigated,which has been effectively applied in the fields of repeatable printing and data encryption.The main research contents are as follows:1.The design and preparation of water-jet printing paper based on Ir?III?complexes and Eu³⁺for optical information printingA new class of Ir?III?complexes has been designed and synthesized for effectively sensitizing Eu³⁺.By utilizing the tunable metal-ligand coordination between Ir?III?complex and Eu³⁺by water,a novel kind of water-jet printing paper has been prepared for information recording and data encryption with high resolution and contrast.By comparing four Ir?III?complexes with different ancillary ligands,the sensitization efficiency of Eu³⁺has been optimized and the excitation wavelength of Eu³⁺can be extended to visible light.After mixing Ir?III?complex and Eu³⁺in the molar ratio of 1:4 on filter paper,the printing paper can be successfully prepared.Pure water is used as the ink to print the information on the paper,which can break lanthanide-ligand coordination bond and result in the luminescence change of the paper.More importantly,after doping highly luminescent BODIPY dye into the printing paper,the information can be successfully covered,which effectively realizes the information encryption.Finally,by using luminescence lifetime imaging technology,the hidden information can be read clearly,which provides a new perspective for developing more efficient optical information printing and encryption technology.2.The design and preparation of rewritable paper based on terpyridine-europium complexes for optical information printingA series of novel terpyridine-europium complexes have been designed and synthesized,and a novel rewritable water-printing paper has been prepared based on the water-induced dynamic metal-ligand coordination between terpyridine ligands and Eu³⁺.By comparing two Eu?III?complexes with different antenna ligands,a more suitable Eu?III?complex is chosen.After coating Eu?III?complexes on filter paper,the printing paper can be successfully prepared.By utilizing pure water as the ink,the repeatable printing can be effectively realized.In addition,in comparation of water as ink,the thermal stability of the printing pattern can be improved with PBS buffer as ink.Thus,after using both water and PBS buffer solution as inks to record the information,the recorded information can be different before and after heating,which achieves the effective data encryption and decryption.