Systhesis And Upconversion Luminescent Properties Of Yb/Er Doped Neodymium Vanadate Polycrystals

Upconversion luminescent materials can convert long wavelength excitation light into short wavelength emission light,which could be widely applicated in traditional optical display,solar cells,photocatalysis and many other fields.In this paper,near-infrared upconversion properties and thermal sensitivity of NdVO₄ micron materials were studied.The main researches are as below.NdVO₄ polycrystalline materials were synthesized via hydro-thermal method,the effect of synthesis process on material structure and upconversion luminescence performance was studied and the upconversion luminescence mechanism of NdVO₄ polycrystalline was also analyzed.Though phase analysis and microstructure analysis combined with FTIR,UV-Vis and upconversion luminescent tests,it could be determined that NdVO₄ with excellent upconversion performance can be synthesized at p H=2,180 ? for reacting temperature,24 hours for reacting time and 2 for reacting ratio?Nd3+/VO43-?.And the near infrared upconversion mechanism was determined through the fluorescent power curve test and photon number analysis.The upconversion luminescent property of NdVO₄ polycrystal was enhanced by Er³⁺ and Yb³⁺ doping,the optimal doping concentration was determined to be 18 mol% for Yb³⁺ and 12 mol% for Er³⁺,respectively.The photon avalanche luminescence mechanism and energy-level migration mode of NdVO₄:?Yb?/Er polycrystalline materials were analyzed and the upconversion luminescent property of polycrystalline materials was improved by changing the luminescence mechanism.Based on NdVO₄: Yb/Er polycrystalline materials with optimal upconversion luminescent performance,the effect of temperature on the upconversion luminescent intensity was studied.The quantitative relationship between the fluorescence intensity ratio and temperature was determined.The temperature detection of composite model was realized by the temperature sensitivity analysis of temperature-coupled energy level and non-temperature-coupled energy level.The temperature sensitivity was calculated and the maximum relativity sensitivity reaches 0.49% K^-1 at 650 K,which is of potential application in the field of temperature sensors.