【摘要】：作為層狀主客體化合物的新成員,層狀稀土氫氧化物(LREHs)結(jié)合了具有豐富物理化學(xué)性質(zhì)的稀土元素和廣泛可調(diào)性的客體陰離子。這類化合物已經(jīng)吸引了大量的研究關(guān)注,而且在光學(xué)、催化、生物醫(yī)藥等各個(gè)領(lǐng)域存在潛在的應(yīng)用價(jià)值。本文介紹了層狀稀土氫氧化物的合成、結(jié)構(gòu)表征、剝離及其對(duì)有機(jī)芳香化合物的熒光檢測(cè)研究。我們分別合成了鈰、釤、銪、鋱、鏑五種稀土元素的層狀氫氧化物,并且通過(guò)對(duì)它們進(jìn)行元素分析、X射線能譜(EDX)及稀土滴定等表征確定了它們的組成式,如下:1:Ce_2(OH)_4.1(SO_4)0.9·2.3H_2O2:Sm(OH)_(2.6)Cl_(0.4)·1.8H_203:Eu(OH)_(2.6)Cl_(0.4).1.4H_204:Tb(OH)_(2.6)Cl_(0.4)·1.OH_205:Dy(OH)_(2.5)Cl_(0.5)·0.5H_20通過(guò)TEM和SEM表征,進(jìn)一步證明合成了層狀稀土氫氧化物,并且清晰的觀察到它們的形貌。層狀氫氧化銪(LEuH)形狀接近長(zhǎng)方體形,尺寸較大且大小均勻,長(zhǎng)約為106-207nm,寬約為52-167nm,厚度約為23.6nm。層狀氫氧化鈰呈片狀,形狀為菱形,其大小尺寸不一,棱長(zhǎng)大在96.6nm-1.0μm,厚約11.5nm。層狀氫氧化鋱呈片狀,形狀尺寸不均一,形狀接近正方形,尺寸范圍在222-606nm,片較厚,厚度約為54.4nm。層狀氫氧化釤尺寸較大,大約(2.5)μm,且較薄,大約4-5nm厚,多處有折疊現(xiàn)象;層狀氫氧化鏑形貌較好,大小居中,為180nm左右,厚度較薄,為20nm左右,而且呈花狀結(jié)構(gòu),形貌獨(dú)特。熒光測(cè)定表明,合成的層狀氫氧化物具有明顯的稀土元素特征峰,且發(fā)光強(qiáng)度較強(qiáng)。為了進(jìn)一步研究氫氧化銪的性質(zhì),我們又通過(guò)不同方法對(duì)其進(jìn)行了剝離實(shí)驗(yàn),并且通過(guò)TEM、SEM和XRD等表征證明其被剝離完全,最后測(cè)剝離后的熒光性質(zhì),發(fā)現(xiàn)完全剝離后,其熒光強(qiáng)度增強(qiáng)。然后我們又用對(duì)苯二甲酸(P-PTA)對(duì)LEuH進(jìn)行了表面修飾,通過(guò)調(diào)控反應(yīng)溫度、對(duì)苯二甲酸和LEuH的摩爾比來(lái)觀察其熒光強(qiáng)度的變化趨勢(shì),發(fā)現(xiàn)隨著對(duì)苯二甲酸修飾量的增加,LEuH的熒光強(qiáng)度逐漸增強(qiáng)。通過(guò)元素分析、差熱-熱重分析(DTA-TG)、紅外光譜分析證實(shí)對(duì)苯二甲酸成功地修飾到了 LEuH表面。且TEM表明,LEuH的形狀大小保持良好沒(méi)有損壞。三價(jià)稀土離子通常能為客體分子提供路易斯酸性位點(diǎn),增強(qiáng)主客體之間的相互作用,可以作為很好的熒光檢測(cè)材料。因此,我們用LEuH來(lái)檢測(cè)p-PTA、2,6-吡啶二羧酸(DPA)等有機(jī)芳香化合物。p-PTA羧酸根的氧原子會(huì)與LEuH表面的Eu~(3+)發(fā)生配位,從而增大LEuH的熒光強(qiáng)度。理論上,DPA羧酸根的氧原子也會(huì)與Eu~(3+)發(fā)生配位,從而增強(qiáng)LEuH的熒光強(qiáng)度。但實(shí)驗(yàn)結(jié)果表明,LEuH能夠用來(lái)檢測(cè)p-PTA,但尚不能對(duì)DPA進(jìn)行檢測(cè)。
[Abstract]:As a new member of layered host-guest compounds, layered rare earth hydroxide (LREHs) combines rare earth elements with rich physical and chemical properties and widely adjustable guest anions. These compounds have attracted a lot of research attention, and have potential application value in optics, catalysis, biomedicine and other fields. In this paper, the synthesis, structure characterization, stripping and fluorescence detection of layered rare earth hydroxide are introduced. The layered hydroxide of cerium, samarium, europium, terbium and dysprosium were synthesized and their composition was determined by elemental analysis, X-ray energy dispersive spectroscopy (EDX) and rare earth titration. As follows: 1:Ce_2 (OH) _ 4.1 (SO_4) 0.9. 2.3H _ 2O2:Sm (OH) _ (2.6) Cl_ (0.4) 1.8H_203:Eu (OH) _ (2.6) Cl_ (0.4). 1.4H_204:Tb (OH) _ (2.6) Cl_ (0.4) 1.OH_205:Dy (OH) _ (2.5) Cl_ (0.5) 0.5H_20 was characterized by TEM and SEM. It is further proved that layered rare earth hydroxide has been synthesized and their morphology has been clearly observed. The shape of layered europium hydroxide (LEuH) is close to the cuboid shape, the size is large and uniform, the length is about 106 nm, the width is about 52 鈮，

本文編號(hào)：2504850