碱土稀土氟化物超细纳米晶的制备和发光性能分析-preparation and luminescent properties analysis of alkaline earth rare earth fluoride ultrafine nanocrystals.docxVIP

AbstractLanthanide (Ln) doped UC nanocrystals are widely used in laser, color display, biological molecules detection, cell imaging, solar cells, NMR developer and scintillator various specific field due to their multiple characteristics such as narrow luminescence band, high color purity, sharp optical absorptivity, low phonon energy and high conversion efficiency. Especially, potential application in biomedicine has made these nanocrystals attract much attention in recent years. Owing to the unique UC property, converting low energy irradiation to high energy emissions, the lanthanide doped UC nanocrystals have many unique advantages in biomedical imaging, including deep penetration owing to the excitation of NIR light, low radiation damage, and weak auto-fluorescence, compared with the conventional fluorescent nanomaterials such as organic dyes and quantum dots. It is well known that the properties of nanocrystals depend highly on their phase, size, and shape. However, there are many factors affecting crystal growth, mainly including reaction time, temperature, PH of reaction environment and ratio concentration of reaction precursor. In order to explore the evolution law of phase, size, and shape of nanocrystals and the influence of phase, size, and shape on UC luminescence property, BaxYb1-xF3-x nanocrystals are synthesized and studied systematically the evolution law of phase, size, shape and luminescence property of nanocrystals. The main contentsare listed as follows:Monodisperse BaxYb1-xF3-x: 1% Er NCs with different proportion of the reaction precursor Ba2+ and Yb3+are synthesized by a solvothermal method. When other experiment parameters are constant, the evolution laws of phase, size and shape of as-synthetized nanocrystals are studied by varying ratio of reaction precursor Ba2+ and Yb3+. The influence of Yb3+ concentration, phase, size and shape etc. on upconversion emission property of BaxYb1-xF3-x nanocrystals is studied by doping Er3+.Monodisperse Bax