以溶膠-凝膠法製備銪鏑共摻雜鋁酸鍶螢光粉及其光致發光特性研究

Sol-Gel Preparation and Photoluminescence Properties of Eu, Dy Co-Doped Strontium Aluminate Phosphors

林聖鈞(Lin Sheng-Jun)

指導教授 ： 張莉毓

國立屏東科技大學/工學院/機械工程系所/碩士(2022年)

https://doi.org/10.6346/NPUST202200434

摘要

本研究是以溶膠-凝膠法製備合成SrAl2O4之螢光粉體，並個別摻雜活化劑Eu及Dy以及Eu-Dy共摻雜，研究不同摻雜濃度及不同煆燒溫度下對粉體之結構特性及性質影響。研究分析包括，X-Ray繞射分析(XRD)、掃描式電子顯微鏡(SEM)、穿透式電子顯微鏡(TEM) 等材料分析及紫外-可見光譜(UV-Vis)和螢光光譜分析(PL)等光學特性分析來探討其結構及性質。
XRD分析結果，利用溶膠-凝膠法可於900 ℃煆燒即可得純相之SrAl2O4粉體，屬於單斜晶系卡號NO. 34-0379，且以較高溫度1100 ℃煆燒，摻雜濃度較高Eu離子會使其產生EuSrAl3O7相出現，而共摻雜之樣本於高溫煆燒其對活化劑離子固溶程度又相較於單摻雜樣本低。SEM結果顯示，摻雜不同活化劑離子及不同濃度皆對於SrAl2O4其表面型貌無明顯改變。TEM結果顯示，晶粒外觀型態與SEM觀察近乎一致，以晶粒及晶粒間相互連接型呈不規則之晶體型貌，經繞射點及高解析圖比對後皆可確定為SrAl2O4晶體結構，但以高溫1100 ℃煆燒摻雜7% Eu之樣本會改變其SrAl2O4主體結構。PL結果顯示，摻雜Eu之樣本最佳激發波長為259 nm，可得其最佳放射波長617 nm，為Eu3+離子5D0 →7F2電子躍遷所造成，以摻雜7% Eu於1100 ℃煆燒之樣本放射波長最強，繪製其CIE色度座標圖顯示其發射顏色為橙紅光。摻雜Dy離子之樣本，並未觀測到以Dy3+為主要放射波段之峰值，繪製其CIE色度座標圖，以藍光為其發光顏色。共摻雜之樣本下顯示Dy3+離子能增強以Eu3+離子為主要放射中心之放射峰，且以900 ℃煆燒下共摻雜1% Eu-1% Dy之樣本效果最佳，繪製其CIE色度座標圖，以粉紫色之發光為主。

關鍵字

SrAl2O4 ； 銪摻雜 ； 螢光粉 ； 鏑摻雜 ； 溶膠-凝膠法

並列摘要

In this study, the phosphor powder of SrAl2O4 was prepared and synthesized by sol-gel method, and the activators Eu and Dy and Eu-Dy were individually doped. Structural properties and properties. Research analysis includes X-Ray Diffraction Analysis (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and other material analysis as well as ultraviolet-visible spectroscopy (UV-Vis) and fluorescence spectroscopy (PL) and other optical properties analysis to explore its structure and properties.
It can be seen from XRD analysis that pure SrAl2O4 powder can be obtained by calcination at 900 ℃ by sol-gel method, which belongs to monoclinic system, and the doping concentration is higher at higher temperature calcination. The presence of Eu ions will cause the appearance of EuSrAl3O7 phase, and the co-doped samples have a lower degree of solid solution to the activator ions than the single-doped samples when calcined at high temperature. The SEM results show that the surface morphology of SrAl2O4 has no obvious change in doping with different activator ions and different concentrations. The TEM results show that the appearance of the grains is almost the same as the SEM observation. The grains and the interconnection between the grains are irregular crystals. After comparing the diffraction points and high-resolution images, it can be determined to be SrAl2O4 crystals structure, but the sample doped with 7% Eu at high temperature 1100 ℃ will change its main structure of SrAl2O4. The PL results show that the optimal excitation wavelength of the sample doped with Eu is 259 nm, and the optimal emission wavelength can be obtained at 617 nm, which is caused by the electronic transition of Eu3+ ions 5D0 →7F2. The wavelength is the strongest, and its CIE chromaticity coordinate diagram shows that its emission color is orange-red light. For samples doped with Dy ions, no peaks with Dy3+ as the main emission band were observed, and their CIE chromaticity coordinates were drawn, and blue light was used as the emission color. The co-doped sample shows that Dy3+ ions can enhance the emission peak with Eu3+ ions as the main emission center, and the sample co-doped with 1% Eu-1% Dy at 900 ℃ has the best effect, and its CIE chromaticity is plotted The coordinate map is dominated by pink and purple light.

並列關鍵字

SrAl2O4 ； Eu3+ ； Phosphors ； Dy3+ ； Sol-Gel Method

參考文獻

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