【摘要】：近年來納米材料的制備方法研究逐漸成為科學熱點之一。在眾多的制備方法中,超聲化學法在納米材料的制備中表現(xiàn)出獨特的性能。本論文利用超聲溶膠-凝膠法制備了稀土β-二酮配合物摻雜的二氧化硅凝膠以及稀土 Pr3+摻雜的二氧化鈦納米材料,并通過光聲光譜(PA)、熒光光譜(PL)、X射線衍射(XRD)等表征手段對超聲制備的樣品性能進行了研究,同時研究了室溫離子液體溶劑中的超聲空化機理。本論文主要由六個章節(jié)組成:第一章簡要地概述了納米材料的分類、特性和相關(guān)的常見制備方法。介紹了聲化學及其在納米材料制備中的應用,分析了超聲化學法制備納米材料的內(nèi)在機理,即超聲空化效應。并給出本課題的研究內(nèi)容及意義所在。第二章介紹了納米材料的分析方法,包括X射線衍射分析(XRD)、熒光光譜(PL)、透射電子顯微學(TEM)和光聲光譜法(PAS)。并著重回顧了光聲光譜技術(shù)的歷史背景、基礎理論和應用領(lǐng)域等。第三章介紹了稀土配合物的光致發(fā)光現(xiàn)象,并通過超聲溶膠-凝膠法將稀土β-二酮配合物 Ln(btfa)3·2H2O(Ln3+:Eu3+,Sm3+,Tb3+btfa:4,4,4-三氟-1-苯基-1,3-丁二酮)摻雜到二氧化硅凝膠中,采用光聲光譜對稀土配合物在凝膠中的形成進行研究。結(jié)果表明,對于僅在室溫下陳化,干燥的濕凝膠樣品,在β-二酮配體吸收處的光聲強度幾乎完全相同。然而,在經(jīng)過150℃熱處理后,Eu3+、Sm3+、Tb3+配合物摻雜的凝膠樣品在配體吸收處的光聲強度依次增強,不同的光聲強度通過熒光光譜的分析得到了解釋,熒光光譜的分析結(jié)果與光聲光譜基本一致,結(jié)果表明稀土β-二酮配合物在沒有經(jīng)過適當熱處理的硅凝膠中不能形成。最后,基于光聲光譜和熒光光譜的結(jié)果提出了樣品的激發(fā)馳豫模型。第四章,首先介紹了納米二氧化鈦材料的研究進展以及稀土離子摻雜二氧化鈦的優(yōu)良特性。然后通過超聲溶膠-凝膠法制備了 Pr3+摻雜的二氧化鈦納米材料,并通過使用Pr3+離子作為光聲探針來研究相變期間樣品結(jié)構(gòu)的變化。結(jié)果表明,對于在80℃下加熱的凝膠樣品,Pr3+的配位環(huán)境與其水相離子相似,Pr3+的f-f躍遷隨著凝膠到銳鈦礦的轉(zhuǎn)變展現(xiàn)出了持續(xù)的紅移,說明Pr3+鍵的"共價性"增加。然而,對于在ll00℃下鍛燒的樣品,Pr3+的f-f躍遷顯示出明顯的藍移,這可歸因于在銳鈦礦到金紅石轉(zhuǎn)變期間Pr3+離子與外表面分離,形成Pr4Ti9O24。最后還討論了摻雜的Pn3+離子對樣品的銳鈦礦相的穩(wěn)定作用。第五章,介紹了液體中的超聲空化機理,以Flynn修正的R-P聲空化方程對室溫離子液體1-丁基-3-甲基咪唑四氟硼酸鹽([Bmim][BF4])中的空化機理進行了空化動力學數(shù)值模擬,分析了超聲驅(qū)動聲壓幅值、驅(qū)動頻率、空化氣泡的初始半徑等相關(guān)參數(shù)對空化效應的影響,并且研究了在變溫情況下離子液體中的獨特的空化特性。第六章,對全文的工作進行總結(jié),并對今后的工作進行展望。
[Abstract]:In recent years, the preparation of nano-materials has gradually become one of the scientific hotspots. Among the many preparation methods, ultrasonic chemistry shows unique properties in the preparation of nano-materials. In this paper, silica gel doped with rare earth 尾-diketone complex and TIO _ 2 nano-material doped with rare earth Pr3 were prepared by ultrasonic sol-gel method. The (PL), fluorescence spectra of rare earth 尾-dione complex and rare earth doped titanium dioxide were obtained by photoacoustic spectroscopy (PA),). The properties of the samples prepared by ultrasound were studied by X-ray diffraction (XRD) and the mechanism of ultrasonic cavitation in room temperature ionic liquids was also studied. This paper mainly consists of six chapters: chapter one briefly summarizes the classification, properties and related common preparation methods of nano-materials. The sonochemistry and its application in the preparation of nano-materials are introduced. The intrinsic mechanism of ultrasonic chemical synthesis of nano-materials is analyzed, I. E., ultrasonic cavitation effect. The research content and significance of this topic are also given. In chapter 2, the analytical methods of nano-materials are introduced, including X-ray diffraction analysis of (XRD), fluorescence spectrum, (PL), transmission electron microscopy (TEM) and photoacoustic spectroscopy (PAS). The historical background, basic theory and application fields of photoacoustic spectroscopy are reviewed. In chapter 3, the photoluminescence of rare earth complexes Ln (btfa) 3 路2H2O (Ln3: Eu3, Sm3, Tb3 btfa:4,4,) was studied by ultrasonic sol-gel method. 4-trifluoro-1-phenyl-1, 3-butanedione (4-trifluoro-1-phenyl-1, 3-butanedione) was doped into silica gel. The formation of rare earth complexes in silica gel was studied by photoacoustic spectroscopy. The results show that the photoacoustic intensity of dry wet gel samples aged only at room temperature is almost the same at the absorption site of 尾-Dione ligand. However, after heat treatment at 150 鈩，

本文編號：2472391