The Preparation And Optical Properties Of Environment-firendly And Energy-saving Perovskite Quantum Dots Glass And Their Application In White LED

White light-emitting diodes has been payed more attention due to their advantages such as environmental protection,long life,high efficiency and low cost.Particularly,all inorganic perovskite CsPbX₃（X=Cl,Br,I）nanocrystals show excellent optical properties and great application potential in the field of all kinds of photoelectric devices because of its full spectrum,narrow emission,high quantum yield,excellent color adjustable optical properties.However,the CsPbX₃（X=Cl,Br,I）colloid which prepared by the traditional hot injection method extremely unstable,and it is difficult to achieve long-term stability when present in the air,only exists in some nonpolar solution,such as acetone,etc.,and it is difficult to realize the white light and polychromatic emission attribute to the anion exchange.Therefore,how to improve the stability of CsPbX₃（X=Cl,Br,I）nanocrystals and reduce anion exchange has become a hot research topic nowadays.In this paper,a series of luminescence adjustable and stable CsPbX₃（X=Cl,Br,I）nanocrystalline glass materials are prepared by using the traditional thermal melting method and monolithic crystallization method.Then a series of characterization methods were used to investigate the microstructure and luminescence properties of these luminescent material.And finally,the photoelectric properties of this material in the application of white LED have been deeply studied though matching with commercial InGaN blue chips.The specific content is divided into two parts as follows:1.The rare earth ions Tb³⁺doped CsPbBr₃ perovskite nanocrystalline glasses were prepared by the traditional thermal melting method.All the samples were characterized by means of XRD,XPS,projection electron microscope,fluorescence spectrum and absorption spectrum.The results prove that CsPbBr₃ nanocrystals were steady uniform dispersion in zinc borosilicate glass substrate,and the Pb²⁺successfully replaced by the rare earth ions Tb³⁺.And a slight of red-shift in the main peak of CsPbBr₃ was occured owing to the energy transfer between CsPbBr₃ and Tb³⁺.The problem of red light defect was solved by introducing rare earth ions Eu³⁺,and the tunability of luminescence realized by adjusting the doping ratio of rare earth ions.Importantly,Tb³⁺and Eu³⁺co-doped CsPbBr₃ glasses showed a series of satisfactory fluorescence properties due to the energy transfer between CsPbBr₃,Tb³⁺and Eu³⁺.Finally,white LED was successfully prepared by matching with InGaN blue chip.Under the current of 20 mA,the CIE color coordinate was located at（0.3335,0.3413）,the color rendering index was as high as85.7,the light efficiency reached 47.6 lm/W,and the correlated color temperature was as low as 4945 K.The results of the study strongly proves that the important feasibility of rare earth ions Tb³⁺and Eu³⁺co-doped CsPbBr₃ glass as a new luminescent material in solid warm light source.2.We further prepared the rare earth ion Tb³⁺doped CsPbI₃perovskite nanocrystalline glass according to the method of preparing Tb³⁺and Eu³⁺co-doped CsPbBr₃ glass.The related characterization results prove that Tb³⁺ions were introduced into the lattice of CsPbI₃glass successfully.And the luminous adjustable CsPbI₃:xTb³⁺glass was obtained by adjusting the quality percentage of Tb³⁺/Pb²⁺.All the samples not only maintained the excellent luminescence performance of CsPbI₃solution but also significantly improved the stability of quantum dots.Finally,the white LED device prepared by matching CsPbI₃:xTb³⁺glass directly with InGaN blue light chip,which indicated that the all-inorganic CsPbI₃:xTb³⁺glass provides many possibilities for the application of high performance,low energy consumption and environment-friendly white light LED.