本文選題：稀土上轉(zhuǎn)換　切入點：CaMoO_4　出處：《海南大學》2015年碩士論文　論文類型：學位論文

【摘要】：稀土上轉(zhuǎn)換熒光納米材料由于光穩(wěn)定性強,發(fā)射帶窄,熒光壽命長,可用近紅外光源連續(xù)激發(fā)等優(yōu)點,使其在光纖、生物成像、載藥、太陽能電池、顯示器件中有潛在應(yīng)用,從而吸引了廣泛關(guān)注。微波輔助法是一種新型的上轉(zhuǎn)換熒光材料的制備方法,具有操作簡單,快速,高效節(jié)能,省時,無污染,能夠在短時間內(nèi)合成結(jié)晶度高、顆粒尺寸小、分散均勻的納米材料等特點。金屬鉬酸鹽的微波介電常數(shù)和其吸收特性十分利于通過用微波法制備出復(fù)雜幾何結(jié)構(gòu),所以本文采用了微波輔助法合成了鉬酸鈣上轉(zhuǎn)換材料。 采用掃描電子顯微鏡、X射線衍射儀、透射電子顯微鏡和熒光光譜儀對樣品的形貌、晶體結(jié)構(gòu)、發(fā)光性質(zhì)進行表征,研究了不同因素(pH、微波時間、燒結(jié)溫度、微波介質(zhì))對其發(fā)光性能的影響。CaMoO4:Er~(3+)/Yb~(3+)樣品的熒光光譜520-540n1n,540-570nm兩個區(qū)域范圍分別對應(yīng)2~H11/2→4I15/2,4S3/2→4I15/2(?)能級躍遷,樣品發(fā)射出純度較高的綠光。稀土元素(?).Er比為9：1時,熒光強度最大。當固定微波時間(9mmin),燒結(jié)溫度(800℃)和微波介質(zhì)(乙二醇),改變pH,pH為3時熒光強度最強；當固定燒結(jié)溫度(800℃),pH(pH=7)和微波介質(zhì)(乙二醇),改變微波時間,微波時間為9min熒光強度最強；當固定微波時間(9min),pH(pH=7)和微波介質(zhì)(乙二醇),改變燒結(jié)溫度,燒結(jié)溫度為800℃樣品的熒光強度最強；當固定微波時間(9min),燒結(jié)溫度(800℃)和pH(pH=7),微波介質(zhì)為油酸時熒光強度最強。當選擇發(fā)光中心為Ho3+.Tm3+,敏化離子是Yb3+,且Ho3+/Tm3+/Yb3+的摻雜比例分別是0.8：0.2：15時,成功制備得到了白光發(fā)射的鉬酸鈣熒光材料。
[Abstract]:Due to the advantages of strong optical stability, narrow emission band, long fluorescence lifetime and continuous excitation by Near-infrared light source, rare earth up-conversion fluorescent nanomaterials have potential applications in optical fiber, biological imaging, drug loading, solar cells and display devices. Microwave assisted method is a new preparation method of up-conversion fluorescent material, which has the advantages of simple operation, fast operation, high efficiency and energy saving, time saving, no pollution, high crystallinity and small particle size in a short time. The microwave dielectric constant and absorption properties of molybdate are favorable to the preparation of complex geometry by microwave method, so the microwave assisted method is used to synthesize calcium molybdate upconversion material. The morphology, crystal structure and luminescent properties of the samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fluorescence spectrometer. The pH of different factors, microwave time and sintering temperature were studied. Effect of microwave media on luminescence properties of CaMoO _ 4: Ernio _ 3 / Yb _ 3). 鈫，

本文編號：1637504