Synthesis And Luminescence Property Of Green Emitting Phosphor LaPO₄:Ce³⁺,Tb³⁺

LaPO₄:Ce³⁺,Tb³⁺?LAP?phosphor possesses good chemical stability and high luminous efficiency.It is widely usedin rare earth trichromatic energy-saving lamps?especially straight fluorescent tubes?and LCD backlight with cold cathode fluorescent lamps.However,currently,the research study on LaPO₄:Ce³⁺,Tb³⁺ are mostly focused on the synthesis of high temperature solid state method and the morphology of phosphor particles cannot be tuned efficiently,which limits its further extended application.In the present work,we useco-precipitation method to synthesize the LAP and examine the effects of complexinig agents,surfactants,heat treatment temperature and pH value on the morphology and luminescent property of the products.We also make comparison of the luminescent property of the phosphors prepared by co-precipitation method and hydrothermal method by using X-ray diffraction?XRD?,scanning electron microscopy?SEM?,excitation and emission spectra and others.The main research results are as follows:?1?The luminescence performance of LaPO₄:Ce³⁺,Tb³⁺ phosphor prepared by co-precipitation method is superior to that of phosphor prepared by hydrothermal method;?2?The effects of different complexinig agents?citric acid,sodium tripolyphosphate and polyvinylpyrrolidone?on the morphology of LaPO₄:Ce³⁺,Tb³⁺ phosphor were investigated.The well-dispersed nanoparticles with stable structure could be obtained through adding appropariate surfactants.The nanoparticles with good dispersibility and stable structure can be obtained by adjusting the amount of complexinig agents.And the particle dispersibility can be further improved by adding surface active agentoleic acid?3?When the samples are prepared by co-precipitation method,it is found that the pH value has great influence on the morphology and output of the samples.The synthesis and luminescence performance can be optimized by adjusting the pH of the solution.?4?Monazite structure of monoclinic phase particles produced by using sodium tripolyphosphate as the complexing agent presents both good luminescence performance and thermal stability.