Synthesizing Li-Al layered double hydroxide (LDH) film on glass substrate/Si wafer and carbon cloth in the ionic solution made of AlLi intermetallic in distilled water

本研究發展一個新穎的方法達到在含有鋁離子與鋰離子的鹼性水溶液中直接生長高方向性鋰鋁層狀雙氫氧化物薄膜形成於玻璃基材、矽基板、碳布基材上，形成層狀雙氫氧氧化物薄膜是在大氣環境下將上述這些基材分別懸吊並浸置於鹼性水溶液中，鋰鋁層狀雙氫氧化物薄膜的組成來自於高密度且自我組裝在基材上的鋰鋁層狀雙氫氧化物薄片，且各薄片接近垂直地站立在基材表面。層狀雙氫氧化物的薄膜厚度隨著浸置處理時間的增加而增厚，也隨著鹼性水溶液的處理溫度升高而增加，因此，薄膜會達到一個穩定的厚度區間。形成鋰鋁層狀雙氫氧化物薄膜達到一個穩定厚度所需的浸置時間與鹼性水溶液的溫度有關。不同處理溫度的鋰鋁層狀雙氫氧化物薄膜在玻璃基材上的紫外光可見光穿透光譜結果在以下說明討論，在玻璃基材上處理溫度為5 oC的鋰鋁層狀雙氫氧化物薄膜(約1.45 μm的厚度)顯示好的紫外線遮蔽能力(穿透率9.7 %)，在可見光波長範圍的最大穿透率56 %。一個相似的方法也可以發展將鋰鋁層狀雙氫氧化物薄膜形成覆蓋在疏水性與親水性碳布的表面結構，經過處理的碳布纖維將有高密度的鋰鋁層狀雙氫氧化物薄片形成於碳纖維表面上，此處理結果將可以明顯的增大碳纖維表面積；儘管碳布纖維的表面經過形成鋰鋁層狀雙氫氧化物薄膜改質處理，經過處理的疏水性碳布與親水性碳布仍然保持它們原有的疏水特性與親水特性。本研究認為大氣環境中的二氧化碳溶於含有鋁離子與鋰離子的鹼性水溶液中轉變為碳酸根離子以提供形成鋰鋁層狀雙氫氧化物的陰離子，層狀雙氫氧化物各薄片在基材表面上透過成核成長的機制最後形成層狀雙氫氧化物薄膜。This paper describes a novel method to achieve direct growth of highly-oriented Li-Al LDH film on substrates such as glass, Si wafer and carbon cloth in an alkaline Al3+- and Li+-containing aqueous solution. The substrate samples were each hanged, and then immersed in the solution for LDH film formation in ambient atmosphere. The Li-Al LDH film composed of extra high density of Li-Al LDH platelets, each almost perpendicularly standing on substrate surface. The LDH film thickness increased with increasing immersion time and/or with increasing solution temperature. Consequently, the thickness would reach a plateau region during the LDH formation. The time to reach the plateau region depends on the solution temperature. UV-visible transmittance spectra of the Li-Al LDH films on glasses were reported. The LDH film that was fabricated at 5 oC (~1.45 μm in thickness) exhibits good UV shielding ability (only 9.7% UV transparency) and a maxium of 56% transparency in the visible. A similar method can also be employed to develop a Li-Al LDH film covering on both hydrophobic and hydrophilic carbon cloth surface. The fibers of the treated carbon clothes had extra high density of LDH platelets on surface, which leads to the fibers have remarkably large surface area. In spite of the surface modification on the carbon fibers, the treated carbon clothes still retain their original surface properties (e.g., hydrophobicity or hydrophilicity). The study believed that CO2 in the atmosphere dissolved in the alkaline Al3+- and Li+-containing solution to provide CO32- ions for Li-Al LDH formation. Nucleation and growth of each LDH platelets on substrate surface finally resulted in a LDH film.LIST OF CONTENTS ABSTRACT (in Chinese) ………… I ABSTRACT (in English) …………III LIST OF CONTENTS…………… V LIST OF TABLES ……………… VI LIST OF FIGURES………………….VII CHAPTER 1 Introduction……1 CHAPTER 2 Experimental……6 2.1. Preparation of Al3+- and Li+-containing solution……6 2.2. Direct growth of Li-Al LDH on alkaline earth boro-aluminosilicate (AEBA) glass and Si wafer……7 2.3 Direct growth of Li-Al LDH on Carbon Cloth……9 CHAPTER 3 Results and discussion…… 11 3.1. Direct growth of Li-Al LDH on alkaline earth boro-aluminosilicate (AEBA) glass and Si wafer……11 3.2. Direct growth of Li-Al LDH on Carbon Cloth……16 CHAPTER 4 Conclusions……20 REFERENCES…… 3

METHOD FOR PREPARING SELF-ASSEMBLED LAYER ON A SURFACE OF A NON-METALLIC MATERIAL

一種形成自組裝層狀雙氫氧化物薄膜的方法，包含將一非金屬基材浸置於一含Li + 陽離子及Al 3+ 陽離子的澄清水溶液中，在大氣環境下於基材表面形成自組裝鋰-鋁層狀雙氫氧化物

METHOD FOR PREPARING LAYERED DOUBLE HYDROXIDES

一種快速製備層狀雙氫氧化物的方法，包含提供一含Li + 陽離子及Al 3+ 陽離子的水溶液，再於此水溶液中加入一不含鋰鹽或鋁鹽之夾層陰離子起使物，夾層陰離子起使物之陰離子可與Li + 、Al 3+ 陽離子結合，形成一層狀雙氫氧化物Li-Al LDH

Preparation the ionized alkaline aqueous solution containing Al3+ and Li+ ions titration on glass substrate growth the transparent film of Li-Al layered double hydroxide

本實驗是利用鋰鋁介金屬化合物(AlLi IMC)與去離子水，製備出含有Al3+/ Li+之鹼性離子水溶液，利用水溶液以滴定及直接浸置的方式，並藉由大氣環境中二氧化碳溶於水溶液而提供的CO32-離子，控制不同的溫度、滴定量或浸置方式讓其自然反應及定時反應，於玻璃基材上成長鋰-鋁層狀雙氫氧化物(Li-Al Layered double hydroxide)透明薄膜，後續稱為Li-Al LDH。由SEM結果顯示於玻璃基層上所長成的Li-Al LDH薄膜都甚為均勻，Li-Al LDH片狀結構尺寸均隨著溶液溫度、滴定量的增加而變大。在各溫度下滴定定時反應40分鐘後即可長出Li-Al LDH薄膜，且能明顯的使球狀結構數量減少，在溫度為5 ℃所長成的Li-Al LDH透明薄膜於可見光波長範圍的穿透率可達99 %以上，且表面疏水性明顯提高並優於原玻璃基材。另當以熱蒸鍍法蒸鍍鋁膜並沉積於Li-Al LDH薄膜上方時，藉由四點探針薄膜電阻量測結果顯示，其電流傳導因路徑增加，薄膜片電阻值亦隨之增加。This study prepared the ionized alkaline aqueous solution containing Al3+ and Li+ ions by mixing lithium-aluminum intermetallic compounds (AlLi IMC) with DI-water. The surface of glass substrate was covered with the aqueous solution by the method of titration and immersion. The growth of the transparent film of lithium-aluminum layered hydroxide (Li-Al layered double hydroxide, hereafter Li-Al LDH) on the glass substrate was generated by the reaction of the Al3+ and Li+ -containing alkaline aqueous solution with CO32- ion from carbon dioxide in atmosphere. The type of reactions could be spontaneous or timing effect, which can be controlled by different temperature setup, amount of solution in titration, or the immersion method. The results show the Li-Al LDH films on the glass substrate are very uniform by the SEM examination. The Li-Al LDH sheet size increases with the increasing solution temperature and amount of solution in titration. It shows that the Li-Al LDH films can be developed after 40 minutes of titration at different temperatures and the number of the bulb structure can be reduced apparently. Especially in the temperature of 5 ℃, the Li-Al LDH film demonstrates high transmission rate up to 99 % in the visible wavelength range and surface hydrophobic is markedly improved and better than that of the original glass substrate. When the thermal evaporation aluminum vapor was deposited on the Li-Al LDH film, it shows that the current conduction path increases and the film sheet resistance also increase.中文摘要.................................................ⅰ Abstract.................................................ⅱ 總目錄...................................................ⅲ 表目錄...................................................ⅴ 圖目錄...................................................ⅵ 第一章 前言...............................................1 第二章 實驗步驟與方法.....................................7 2-1 實驗製程方法與設備..................................7 2-2 實驗步驟............................................7 2-2-1 試片的前處理....................................7 2-2-2 水溶液的配製....................................7 2-2-3 滴定法與浸置法的LDH薄膜生成.....................8 2-2-4 物理蒸鍍金屬鍍膜................................9 2-3 掃描式電子顯微鏡與低掠角X光繞射儀...................9 2-4 傅立葉紅外線光譜儀..................................9 2-5 紫外/可見光譜儀....................................10 2-6 接觸角分析儀.......................................11 2-7 四點探針量測儀.....................................11 第三章 結果與討論........................................15 3-1 SEM顯微組織分析................................... 15 3-2 GAXRD結晶結構繞射分析............................. 17 3-3 傅立葉紅外線光譜分析...............................17 3-4 透光性測量分析.....................................18 3-5 接觸角量測分析.....................................19 3-6 四點探針薄膜電阻量測分析...........................20 第四章 結論..............................................41 參考文獻.................................................4

Removal of phosphate from water using Li/Al layered double hydroxide

人類經濟與休閒活動，產生了許多含磷的廢水，這些廢水被排放至表面水體將造成藻類過量增生，並進一步導致水體的優養化。對於水體中的磷的移除，吸附法為最有效的方法之ㄧ。本研究使用的鋰/鋁-層狀雙氫氧化物(Li/Al Layered double hydroxide, Li/Al LDH)由於具有很高的比表面積與陰離子吸附容量(~4.5 mmol g-1)，具有去除環境中磷的潛力。在本研究中將探討水體中的環境因子，包括pH、離子強度與水體中其他競爭陰離子，對Li/Al LDH吸附磷的影響，並結合X光繞射、傅立葉轉換紅外光譜與固態磷-31核磁共振等儀器的輔助，了解Li/Al LDH與磷溶液反應過後其結構所產生的變化，並探討主要的吸附機制。結果發現，在pH 4.5與pH 9.5的環境下，都是以離子交換為主要的反應機制，但是在pH 4.5的環境下還有表面錯合和沉澱反應的發生。在pH 4.5的環境下，競爭離子的親和力大小為SO42->Cl- >Br->NO3-，但是在pH 9.5的環境下，除了SO42-對磷吸附有顯著的抑制外，其於單價競爭陰離子的影響程度皆較小。Phosphorus has been recognized as one of the main nutrients that cause eutrophication in surface water, so many technologies have been developed for phosphate removal from water. Adsorption is one of the major strategies for removing contaminants from water. In order to provide a cost-effective method for phosphate removal, it is essential to have a sorbent that can effectively immobilize phosphate. In this study, the sorption of orthophosphates was investigated for LiAl2(OH)6Cl•xH2O (Li/Al-LDH) which has high surface area and high anion exchange capacity (~4.5 mmol g-1). Sorption experiments were conducted at pH 4.5 and 9.5, at which the predominant species of phosphate are H2PO4- and HPO42-, respectively.In addition, the influence of pH, ion strength and competition ions on phosphate sorption was also investigated. The results showed that phosphates were sorbed by Li/Al LDH mainly through anion exchange at pH 4.5 and 9.5; under acidic condition (pH 4.5), the formations of surface complexes or surface precipitation of phosphate were also revealed by the results of 31P NMR. Competing anions strongly affected the adsorption behavior of phosphate with phosphate adsorption decreasing in the order: SO42->Cl- >Br->NO3- at pH 4.5. However, monovalent competing anions (Cl-、NO3- and Br-) had less influence on phosphate adsorption at pH 9.5.摘要 I Abstract II 目錄 IV 圖次 VII 壹、前言 1 貳、文獻回顧 3 (一) 形成優養化的原因 3 (二) 優養化產生的影響 4 (三) 含磷廢水處理 5 (四) 層狀雙氫氧化物的特性與應用 9 参、材料與方法 13 (一)樣品的合成與結構鑑定 13 (二)動力吸附實驗 13 1. pH值對Li/Al LDH吸附磷酸根離子的影響 13 2.固體濃度對Li/Al LDH吸附磷酸根離子的影響 15 3.不同起始濃度對Li/Al LDH吸附磷酸根離子的影響 16 (三)等溫吸附實驗 16 1.pH對吸附量的影響 16 2.固體濃度對吸附量的影響 17 (1)溶液配製 17 (2)吸附實驗 17 3.競爭陰離子對吸附量的影響 17 (四)測定方法與分析儀器 18 1.鉬藍法(Mobdenum blue method) 18 2.X光粉末繞射儀(X-ray Diffraction) 18 3.傅立葉轉換紅外光譜儀(FTIR) 18 4.固態P-31核磁共振光譜實驗(Solid State 31P-NMR) 19 肆、結果與討論 20 (一) Li/Al LDH基本特性分析 20 (二)動力學吸附實驗 23 1.pH值對Li/Al LDH吸附磷酸根離子的影響 23 2.固體濃度對Li/Al LDH吸附磷酸根離子的影響 25 3.不同起始濃度對Li/Al LDH吸附磷酸根離子的影響 29 (三)等溫吸附實驗 43 1.pH對吸附量的影響 43 2.固體濃度對吸附量的影響 48 3.競爭陰離子對吸附量的影響 53 伍、結論 5