Energy Transfer From Pr³⁺to Er³⁺ In NaYF₄

Quantum cutting is a key of vacuum ultraviolet luminescence materials. There is an important significance for the development of plasma display panel and mercury free fluorescent lamp technology. Pr3+has shown photon cascade emission, but Pr3+1S0-16emission at400which falls in deep violet, that would make life harder for application. The energy transfer is a recipe for improve the luminous efficiency.This thesis is divided into the following sections:1. Fluorescence properties of NaYF4:Pr3+,Er3+were investigated, by comparing the excitation and emission spectra of the obtained specific process of the energy transfer.Pr3+1S0can transfer its energy to Er3+when pumped by186nm; Pr3+3P0can transfer its energy to Er3+when pumped by4666nm.We use the selectivity of excitation to calculate the contribution to the observed spectrum from Er3+through transfer from Pr3+.2. Based on decay curves of NaYF4:Pr3+,Er3+, energy transfer from Pr3+transfer state to Er3+was observed. The life time of Pr3+3P0is19.6us in NaYF4:Pr3+,and the life time of Pr3+3P0is3us in NaYF4:Pr3+,Er3+.The3P0loss it life in NaYF4:Pr3+,Er3+by energy transfer. And the Er3+4S3/2life time pumped with466nm is also studied by calculation. The rise time of Er3+4S3/2equals to decay time of Pr3+3Po. Based on the spectrum of the emission spectrum of the emission peak fitting and score ratio calculation, get the sample in Pr3+to Er3+energy transfer efficiency.3. Study on the effect of matrix for Pr3+to Er3+energy transfer efficiency. In LaF3, Pr3+3Po to Er3+energy transfer efficiency is less than NaYF4. Through the matrix of the lattice parameters, LaF3Pr3+and Er3+ion between the minimum distance is much bigger than NaYF4. This shows that, the efficiency change matrix to reduce the minimum distance between the ions can improve Pr3+to Er3+energy transfer.