Rare Earth Ions Doped Y 2 O 2 S And Y 2Preparation And Properties Of O 3 /Y 2 O 2 S Composite Nanocrystals

As nano science and technology has been developing rapidly in recent years,nano materials which possesses novel optical,electronic,magnetic and mechanical properties has being synthesized constantly.It is well known that the size,morphology and structure of nano materials have tremendous effects on their properties.A good substrate material may also improve luminescence performance obviously.In this paper,Y₂O₃/Y₂O₂S luminescence host materials were synthesized.By doping different rare-earth ions,we successfully obtained a series of luminescence nanomaterial.The luminescence properties as well as applications in the field of DSSCs were investigated.1)The rare earth nanocrystalline precursors were prepared first through the hydrothermal method via adjusting and controlling the reaction temperature and time.Then Y₂O₃/Y₂O₂S:Eu³⁺composite nanocrystals were successfully synthesis by Sulfur flux method.The luminescent properties of Y₂O₃/Y₂O₂S:Eu³⁺composite nanocrystals were studied.The results show that the Y₂O₃/Y₂O₂S:Eu³⁺composite nanocrystals have different luminescent properties.Compared with Y₂O₃:Eu³⁺,the emission peaks of⁵D₀?⁷F₀ and ⁵D₀?⁷F₁ showed a little red shifted.2)Y₂O₃/Y₂O₂S:Yb³⁺/Er³⁺composite nanocrystals were synthesized and their upconversion luminescence properties were studied.The emission peaks of ²H_11/2?⁴I_15/2??527nm?,⁴S_3/2?⁴I_15/2??550nm?and ⁴F_9/2?⁴I_15/2??660nm?were observed under 980nm light excitation.3)The obtained Y₂O₃/Y₂O₂S:Eu³⁺composite nanocrystals were introduced into the photoanode of the dye-sensitized solar cells?DSSCs?.The electrochemical results indicate that Y₂O₃/Y₂O₂S:Eu³⁺composite nanocrystals could improve the efficiency of the cells.The efficiency of TiO₂-Y₂O₃/Y₂O₂S:Eu³⁺composite battery is⁸.38%,which is¹2%higher than that of pure TiO₂ battery.The various factors of battery efficiency enhancement was discussed via dynamic light scattering and diffuse reflectance spectroscopy.