【摘要】：白光發(fā)光二極管(LED)具有節(jié)能環(huán)保、壽命長、響應(yīng)速度快、體積小可進(jìn)行平面封裝等諸多優(yōu)點(diǎn),被公認(rèn)為第四代照明光源。目前,白光LED的實(shí)現(xiàn)方案主要以熒光轉(zhuǎn)換型為主,然而,目前紅粉效率低,且不穩(wěn)定,限制了高顯色指數(shù)、高效率白光LED的發(fā)展,因此,研究近紫外光芯片適用的高效紅粉變的非常重要。本學(xué)位論文主要研究近紫外光芯片用紅色熒光粉,采用一種簡單的溶膠-凝膠法制備了Sr2MgWO6:Eu、Sr2CaMO6:Eu、Sr3WO6:Eu三種體系紅色熒光粉。(1)實(shí)驗(yàn)研究了Sr2MgWO6:Eu體系紅色熒光粉的熒光性能,研究了激活劑濃度與發(fā)光性能的關(guān)系、Sm3+離子的引入對發(fā)光性能的影響以及電荷補(bǔ)償對發(fā)光性能的影響。實(shí)驗(yàn)結(jié)果表明,激活劑濃度在x=0.1時(shí),Sr2-2xMgWO6:2xEu的熒光性能最佳;Sm3+離子在Sr2MgWO6:Eu體系中可以起到優(yōu)質(zhì)敏化劑的作用,Sm3+離子的引入可以拓寬近紫外區(qū)的激發(fā)光譜,并且能明顯的提高發(fā)射強(qiáng)度,而且并未發(fā)現(xiàn)來自Sm3+的特征發(fā)射光譜;采用Li+做電荷補(bǔ)償效果最好,發(fā)射強(qiáng)度約為不做電荷補(bǔ)償?shù)?倍,并且色純最高為98.4%,色坐標(biāo)為(0.66,0.33),非常接近NTSC標(biāo)準(zhǔn)值(0.67,0.33)。此外,Sr2MgWO6:Eu體系紅色熒光粉在465nm光激發(fā)下的發(fā)射強(qiáng)度更大,說明該體系熒光粉也適合應(yīng)用在藍(lán)光芯片上。(2)實(shí)驗(yàn)研究了Sr2CaMO6:Eu體系熒光粉的熒光性能,其激發(fā)光譜與近紫外光芯片有極佳的匹配,電荷遷移帶覆蓋近紫外光區(qū)域,峰值位于~400nm處。實(shí)驗(yàn)結(jié)果表明,激活劑濃度在x=0.04時(shí),Sr2-2xCaMoO6:2xEu的熒光性能最佳;采用Li+、Na+、K+做電荷補(bǔ)償劑均可以提高熒光性能,但Li+、Na+做電荷補(bǔ)償更有利于提高熒光粉的純度;采用W與Mo互補(bǔ)摻雜可以明顯提高熒光性能,并且可以使電偶極躍遷5D0-7F2增強(qiáng),當(dāng)W/Mo比例為1:1時(shí),整體的熒光性能最佳,此外,當(dāng)W引入Sr2CaMoO6:Eu體系熒光粉中,可以使熒光粉的表面形貌更加規(guī)則。(3)實(shí)驗(yàn)研究了Sr3WO6:Eu體系熒光粉的熒光性能,該體系熒光粉在近紫外區(qū)域有極強(qiáng)的激發(fā),發(fā)射效率以及色純度也非常高,是一種優(yōu)質(zhì)的近紫外光芯片用的紅粉。實(shí)驗(yàn)發(fā)現(xiàn),Sr3-xEuxWO6當(dāng)摻雜濃度為x=0.3時(shí),整體效果最佳;Sm3+離子不能起到很好的敏化作用;K+離子是一種優(yōu)質(zhì)電荷補(bǔ)償劑,采用K+做電荷補(bǔ)償可以明顯提高熒光性能,制備的樣品具有極高的色純度,色坐標(biāo)為(0.655,0.339)。
[Abstract]:White light emitting diode (LED) is recognized as the fourth generation lighting source because of its many advantages, such as energy saving and environmental protection, long life, fast response speed, small volume and so on. At present, the realization scheme of white light LED is mainly fluorescence conversion type. However, at present, the red powder efficiency is low and unstable, which limits the development of high color index and high efficiency white light LED. Therefore, it is very important to study the high efficiency red powder conversion suitable for near UV chips. In this thesis, three kinds of red phosphors of Sr2MgWO6:Eu,Sr2CaMO6:Eu,Sr3WO6:Eu system were prepared by a simple sol-gel method. (1) the fluorescence properties of red phosphors of Sr2MgWO6:Eu system were studied experimentally. the relationship between the concentration of activators and luminous properties, the effect of the introduction of Sm3 ions on the luminous properties and the effect of charge compensation on the luminous properties were studied. The experimental results show that when the concentration of activating agent is x 鈮，

本文編號：2498180