Design,Synthesis And Property Of Luminescent Materials In Different Wavelength Bands

The design,synthesis and application of luminescent materials in different wavelength bands are of great significance to the development of organic semiconductors,especially the development of organic light-emitting diodes and organic lasers.In many organic light emitting material systems,ladder-type materials have the advantages of excellent stability,large ?-conjugate plane,etc.,so they play an important role in improving the photothermal stability and gain characteristics of the laser gain medium.In this paper,starting from the design of high-performance organic laser gain medium,a series of ladder-tyle materials are designed and synthesized,which emitting from blue to orange According to introducing high-efficiency light-emitting units,large ?-conjugate planes and using star-shaped molecular design ideas,a series of material systems in organic gain media have been developed with complete structure and excellent performance.At the same time,in view of the lack of organic light-emitting materials and the low efficiency in the near-infrared wavelength region,a series of near-infrared light-emitting material systems were designed and synthesized(1)A series of linear ladder-type molecules LBDT,LIDT and LIDTT were synthesized by introducing triphenylamine as the terminal group and alkylbenzene trapezoidal structure as the skeleton.The results show that the material not only shows good thermal stability,but also has a low ASE threshold.Among them,LBDT and LIDTT have excellent ASE thermal stability,high gain value and low loss.By introducing different ?-conjugated molecule cores,the emmision of materials are successfully achieved from green to orange wavelength band(2)The star-shaped ladder-type macromolecule PyL-n(n=1-3)was successfully constructed Complete chemical structure and high purity,by using pyrene as the intermediate core structure,trapezoids with different conjugated lengths as the skeleton,and capped with diphenyl amine.The results show that materials have high PLQY,low ASE threshold,and excellent ASE thermal stability,indicating that this type of material has broad application prospects as organic gain media(3)A series of near-infrared organic compounds with donor-acceptor structures were synthesized,named IR-n(n=1-5),which was introduced by a rigid large-area acceptor structure closed to thiazoline quinoxaline and naphthalene functional groups,by selected strong electron donor as the donor structure.The material realizes luminescence in the red and near infrared wavelenght bands(617-704 nm)in the solution state.Among them,the emission peak position of IR-1 in the thin film state reached 690 nm.Theoretical calculations show that the HOMO/LUMO energy levels of materials can be effectively separated,and the energy level difference is only about 2 eV.