生物炭（BC）是利用農業、林業、城市的生物質廢棄物材料在低氧環境下高溫燃燒製備而成，因其低成本、資源循環再生、來源豐富且能夠有效減少碳排放等特點，一直以來都得到了大量的關注。BC具有比表面積大、孔隙率高、官能團豐富、化學性能穩定等優點，使其被廣泛的應用於碳基電極材料當中。
五氧化二釩（V2O5）相較其他過渡金屬氧化物成本更低、自然儲備豐富、較多的氧化價態並且擁有較高的理論電容值，是一種很有發展潛力的電極材料。特別是被研究作為超級電容器的電極材料，在電化學電容器碳質材料的替代電極研究中具有較大研究前景。然而V2O5的導電性較差，因此為了克服這一挑戰，本實驗將生物炭與V2O5以四種不同重量比例（10、25、35、50wt% V2O5@BC）組合，合成復合材料作為電容去離子（CDI）系統的正極材料。此外還選用二維過渡金屬碳化物(MXene)作為電容去離子系統的負極材料。利用電化學循環伏安法與阻抗法，分別確定電極材料的比電容和電阻。結果表明，35wt% V2O5 @BC的復合材料在0-1電位窗口和10mV/s 掃速下展現出140F/g的比電容值，相較其他重量比例復合材料以及單一材料的比電容值都有較大的提升。在CDI吸附容量測試中發現，以35wt% V2O5 @ BC復合材料作為正極，MXene作為負極的混合CDI系統對NaCl的去除有較優異的表現。在鹽溶液濃度為5000mg/L的環境下，最高比電吸附容量達到122mg/g。該混合CDI體系在經過100次循環後仍能保持90%的吸附-解吸循環的優異循環性能，證明該電容去離子體系具有優異的耐久性。在與近5年相似材料的研究結果比對發現該體系仍然有較佳的優勢，這些結果表明作為不對稱35% V2O5 @BC // MXene作為混合半鹽水淡化的混合CDI系統的電極，具有較優秀的發展前景。

Biochar (BC) was prepared by burning biomass waste materials from agriculture, forestry, and cities at high temperatures in a low-oxygen condition has been widely used because of its low cost, resource recycling, abundant sources, and ability to reduce carbon emissions effectively. Owning to the advantages in large surface area, high porosity, rich functional groups, and stable chemical properties, BC has been widely used as carbon-based electrode materials.
Compared with other transition metal oxides, vanadium pentoxide (V2O5) possesses a promising electrode material due to lower cost, abundant natural reserves, more oxidation valence states and higher theoretical capacitance value. Especially, the utilization of V2O5 as supercapacitor electrode material is great research prospect for finding the alternative carbonaceous materials in electrochemical capacitors. However, the conductivity of V2O5 is poor, therefore, to overcome this challenge, in this research, the combination of V2O5 and BC were studied in four different weight ratios (10, 25, 35, 50wt% V2O5@BC), which can be used as the positive electrode material for hybrid capacitive deionization (CDI) system. In addition, two-dimensional transition metal carbide (MXene) was selected as the negative electrode material of the CDI system. The electrochemical cyclic voltammetry and impedance were thoroughly conducted to determine the specific capacitance and resistance, respectively, of the electrode materials. As the results, the composite material of 35wt%V2O5 with BC displays a specific capacitance value of 140 F/g at a potential window of 0-1 V and at 10 mV/s. The specific capacitance values of other weight ratio composite materials and single materials have been greatly improved. In the CDI electrosorption capacity test, it was found that the hybrid CDI system with 35wt% V2O5 and BC as the positive electrode and MXene as the negative electrode exhibits excellent performance in the removal of NaCl. In 5000 mg/L, the highest specific adsorption capacity was achieved as 122 mg/g. The hybrid CDI system can still maintain the excellent cycle performance of 90% of the adsorption-desorption cycles after 100 cycles, indicating that the CDI system has excellent durability. Compared with the research results of similar materials in the past 5 years, it is found that this system still has better advantages. These results show that as an electrode of asymmetric V2O5@BC//MXene as a hybrid CDI system for desalination of semi-salt water, there is a better development prospect.

目錄 ⋯⋯⋯⋯⋯⋯⋯⋯v
圖目錄⋯⋯⋯⋯⋯⋯⋯⋯vii
第 1 章 前言⋯⋯⋯⋯⋯⋯⋯⋯1
1.1 前言⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯1
1.2研究動機⋯⋯⋯⋯⋯⋯⋯⋯1
第 2 章 文獻回顧⋯⋯⋯⋯⋯⋯4
2.1 當前水環境問題及永續發展⋯⋯⋯⋯⋯⋯⋯⋯4
2.2 傳統海水淡化技術的發展與應用⋯⋯⋯⋯⋯⋯5
2.2.1 熱能推動的海水淡化技術⋯⋯⋯⋯⋯⋯⋯⋯6
2.2.2 薄膜海水淡化技術 ⋯⋯⋯⋯⋯⋯⋯⋯9
2.3 電容去離子（Capacitive deionization, CDI）技術 ⋯⋯⋯⋯⋯⋯11
2.3.1 電雙層(Electric double layer, EDL)理論⋯⋯⋯⋯⋯⋯⋯⋯13
2.4 電容去離子系統的電極材料⋯⋯⋯⋯⋯⋯⋯⋯16
2.4.2 生物炭（Biochar，BC）⋯⋯⋯⋯⋯⋯⋯⋯20
2.4.3 二維過渡金屬碳化物（MXenes） ⋯⋯⋯⋯⋯⋯⋯⋯22
第 3 章 研究方法 ⋯⋯⋯⋯⋯⋯⋯⋯24
3.1 化學藥劑 ⋯⋯⋯⋯⋯⋯⋯⋯24
3.2 實驗設備 ⋯⋯⋯⋯⋯⋯⋯⋯24
3.3 實驗流程 ⋯⋯⋯⋯⋯⋯⋯⋯25
3.3.1 五氧化二釩與生物炭的復合材料之合成⋯⋯⋯⋯⋯⋯⋯⋯25
3.3.2 二維過渡金屬碳化物（MXenes）的合成⋯⋯⋯⋯⋯⋯⋯⋯27
3.3.3 混合電容去離子系統的組成⋯⋯⋯⋯⋯⋯⋯⋯28
3.4 材料特性鑑定儀器之分析與原理⋯⋯⋯⋯⋯⋯⋯⋯29
3.4.1 X光繞射儀（X-ray Diffractometer，XRD⋯⋯⋯⋯⋯⋯⋯⋯29
3.4.2 掃描式電子顯微鏡（Scanning Electron Microscope，SEM）⋯⋯⋯⋯⋯⋯⋯⋯30
3.4.3 穿透式電子顯微鏡（Transmission electron microscope，TEM）⋯⋯⋯⋯⋯⋯⋯⋯31
3.4.4 拉曼光譜儀（Raman spectroscopy）⋯⋯⋯⋯⋯⋯⋯⋯33
3.4.5 比表面積與孔隙度分析儀(Specific Surface Area and Porosimetry Analyzer，BET)⋯⋯34
3.4.6 傅立葉變換紅外光譜（Fourier-transform infrared spectroscopy, FTIR）⋯⋯⋯⋯⋯⋯36
第 4 章 結果與討論 ⋯⋯⋯⋯⋯⋯⋯⋯38
4.1五氧化二钒与生物炭复合材料之结构分析⋯⋯⋯⋯⋯⋯⋯⋯38
4.2 五氧化二钒与生物炭复合材料之電化學特性分析⋯⋯⋯⋯⋯⋯⋯⋯46
4.3 二維過渡金屬碳化物（MXene）之結構分析⋯⋯⋯⋯⋯⋯⋯⋯49
4.3 MXene之電化學特性分析⋯⋯⋯⋯⋯⋯⋯⋯51
4.4 電容去離子之效能⋯⋯⋯⋯⋯⋯⋯⋯52
Ag@rGO//Na1.1V3O7.9@rGO⋯⋯⋯⋯⋯⋯⋯⋯54
W18O49/Ti3C2 MXene⋯⋯⋯⋯⋯⋯⋯⋯54
第 5 章 結論⋯⋯⋯⋯⋯⋯⋯⋯55
參考文獻⋯⋯⋯⋯⋯⋯⋯⋯57

圖目錄
圖 1 1 實驗架構圖⋯⋯⋯⋯⋯⋯⋯⋯3
圖 2 1 常見的海水淡化技術⋯⋯⋯⋯⋯⋯⋯⋯6
圖 2 2 多級閃蒸技術操作原理[9]⋯⋯⋯⋯⋯⋯⋯⋯7
圖 2 3 多效蒸餾法操作流程[12]⋯⋯⋯⋯⋯⋯⋯⋯8
圖 2 4 正滲透與逆滲透之原理[11]⋯⋯⋯⋯⋯⋯⋯⋯11
圖 2 5 電容去離子的應用[16] ⋯⋯⋯⋯⋯⋯⋯⋯12
圖 2 6 雙電層模型 ⋯⋯⋯⋯⋯⋯⋯⋯15
圖 2 7 CDI電極的材料應用[24]⋯⋯⋯⋯⋯⋯⋯⋯17
圖 2 8 V2O5材料的應用[24] ⋯⋯⋯⋯⋯⋯⋯⋯20
圖 2 9 MXenes合成進展時間表⋯⋯⋯⋯⋯⋯⋯⋯23
圖 3 1五氧化二釩與生物炭復合材料製備流程⋯⋯⋯⋯⋯⋯⋯⋯27
圖 3 2 合成二維過渡金屬碳化物（MXene）之實驗流程⋯⋯⋯⋯⋯⋯⋯⋯28
圖 3 3 布拉格公式示意圖⋯⋯⋯⋯⋯⋯⋯⋯30
圖 3 4 掃描式電子顯微鏡基本構造及功能[33]⋯⋯⋯⋯⋯⋯⋯⋯31
圖 3 5 TEM系統之基本部件組成⋯⋯⋯⋯⋯⋯⋯⋯32
圖 3 6 拉曼光譜儀示意圖[35]⋯⋯⋯⋯⋯⋯⋯⋯34
圖 3 7 六種氮氣等溫吸附曲線[38] ⋯⋯⋯⋯⋯⋯⋯⋯35
圖 3 8 透過氮物理吸附獲得的四種遲滯環類型[38]⋯⋯⋯⋯⋯⋯⋯⋯36
圖 3 9 FTIR部件及工作原理圖⋯⋯⋯⋯⋯⋯⋯⋯37
圖 4 1純BC(a)、純VO（b）以及分別含有20mg、50mg、70mg以及100mg四種不同VO添加量的復合材料VB1(c)、VB2(d)、VB3(e)、VB4(f)的SEM圖像 ⋯⋯⋯⋯⋯⋯⋯⋯40
圖 4 2 VB3的TEM圖譜 ⋯⋯⋯⋯⋯⋯⋯⋯40
圖 4 3 純生物炭、五氧化二釩以及不同比例復合材料之XRD圖譜⋯⋯⋯⋯⋯⋯⋯⋯42
圖 4 4 純生物炭、五氧化二釩以及不同比例復合材料之Raman圖譜⋯⋯⋯⋯⋯⋯⋯⋯43
圖 4 5 純生物炭、五氧化二釩以及不同比例復合材料之FTIR圖譜⋯⋯⋯⋯⋯⋯⋯⋯44
圖 4 6 純生物炭、五氧化二釩以及不同比例復合材料之氮氣吸附-脫附等溫曲⋯⋯⋯⋯⋯⋯45
圖 4 7 VB2 復合材料的XPS圖譜⋯⋯⋯⋯⋯⋯⋯⋯46
圖 4 8 a,b分別為純VO與BC在0到1純正電位下以不同掃速所測得的CV⋯⋯⋯⋯⋯⋯⋯⋯47
圖 4 9 BC與VO正負電位比電容值比較 ⋯⋯⋯⋯⋯⋯⋯⋯48
圖 4 10 復合材料VB1、VB2、VB3、VB4循環伏安曲線⋯⋯⋯⋯⋯⋯⋯⋯48
圖 4 11 純VO與純BC以及四種不同比例復合材料之比電容值曲線⋯⋯⋯⋯⋯⋯⋯⋯49
圖 4 12 純VO與純BC以及四種不同比例復合材料之阻抗圖譜⋯⋯⋯⋯⋯⋯⋯⋯49
圖 4 13 MXene 的SEM圖像⋯⋯⋯⋯⋯⋯⋯⋯50
圖 4 14 （a）MXene的XRD圖譜；（b）MXene的拉曼圖譜；（c）MXene的氮氣吸附-脫附等溫線；（d）MXene孔徑分佈圖 ⋯⋯⋯⋯⋯⋯⋯⋯51
圖 4 15 （a）MXene在不同掃速下的循環伏安曲線⋯⋯⋯⋯⋯⋯⋯⋯52
圖 4 16（a）不同電極組合的CDI脫鹽效果；（b）不同工作電壓下的脫鹽效果；（c）不同鹽濃度下脫鹽的效果⋯⋯⋯⋯⋯⋯⋯⋯53
圖 4 17 35%V2O5@BC// MXene CDI 系統之100圈循環穩定性測試⋯⋯⋯⋯⋯⋯⋯⋯54

表目錄
表 4 1各類材料之BET檢測數據⋯⋯⋯⋯⋯⋯⋯⋯45
表 4 2 VB2@BC// MXene的 SEC與近幾年類似系統相關研究比對⋯⋯⋯⋯⋯⋯⋯⋯54

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