臺灣博碩士論文加值系統

本研究透過低成本、簡易的水熱法合成超級電容器之電極活性材料。以含氮石墨烯做為基底層，在其上生長α-和γ-兩相混合之二氧化錳，並調整錳含量的比例，製備出條狀結構之含氮石墨烯/二氧化錳複合物(x-NGM)。製作元件時，採用PVA/LiCl電解質凝膠膜作為兩電極之分隔層，進而探討電容特性。研究結果表明過高的錳含量不利於離子傳輸和法拉第電荷轉移，其電容特性隨之下降。同時發現過多的質量負載亦會使導電率下降，進而影響超級電容器的電容特性。3-NGM1//G1元件經CV曲線計算，可獲得高達579 F·g-1之比電容。以GCD法在1 A·g-1的電流密度下進行測試，其最高能量密度和功率密度分別為73.6 Wh·kg-1和4400.0 W·kg-1，說明了其具備快速充放電能力，且提供最大的充電容量。為鑑定元件之循環穩定性，採GCD法在1 A·g-1的電流密度下，經2000次的彎曲循環後，其比電容的維持率約86.71 %。本研究之可撓式固態非對稱超級電容器具高度靈活性、循環穩定性，和良好的電容性能，可歸因於兩相混合二氧化錳和含氮石墨烯的協同效應。擬電容材料搭配電雙層電容材料的快速充放電特性，結合兩種電荷儲存機制，有助於提升電荷傳輸、降低電荷轉移阻抗，進而改善電容特性。

In this study, the electrode active materials of supercapacitors were prepared by a low-cost facile hydrothermal approach. The N-containing graphene/MnO2 composites (x-NGM) were obtained by growing α- and γ-phase MnO2 nanostructures on the surface of N-containing graphene. A PVA/LiCl electrolyte gel membrane was employed as the separator between two electrodes for supercapacitors. By changing the content of Mn and adjusting the mass loading of active materials, the capacitance characteristics of various electrodes and devices were investigated. Excessive Mn contents were proven to be detrimental to ion transport and faradaic charge transfer, and inferior capacitance characteristics were thereby resulted. Too much mass loading was also demonstrated to decrease conductivity, leading to worse capacitor performance. After calculation by CV results, the 3-NGM1//G1 device exhibited the highest specific capacitance of 579 F·g-1. The corresponding energy and power densities were 73.6 Wh·kg-1 and 4400.0 W·kg-1, respectively, implying its rapid charge/discharge capacity. After 2000 bending cycles under the current density of 1 A·g-1 by GCD method, the retention rate of specific capacitance was found to be around 86.71 %. The high flexibility, cycling stability, and good capacitance properties could be attributed to the synergistic effect of mixed-phase MnO2 and N-containing graphene. By combining the electric double-layer material with pseudo-capacitance materials, the two charge storage mechanisms were joint to improve charge transfer, conductivity, and thus capacitor performance.

目次
致謝辭 i
摘要 ii
Abstract iii
目次 v
表目次 viii
圖目次 ix
第一章 緒論 1
1.1 前言 1
1.2研究動機 1
第二章 文獻回顧 6
2.1 電雙層電容器 6
2.2 擬電容器 6
2.3 氮摻雜石墨烯應用於超級電容器 9
2.4 氧化錳應用於超級電容器 10
2.5 超級電容器之元件設計 14
第三章 實驗步驟 20
3.1 藥品與材料 20
3.2 儀器設備 21
3.3 實驗方法 22
3.3.1 材料合成 22
3.3.1.1 氧化石墨之製備 22
3.3.1.2 石墨烯之製備 22
3.3.1.3 氮摻雜石墨烯之製備 22
3.3.1.4 氮摻雜石墨烯/二氧化錳複合物之製備 23
3.3.2 超級電容器之電極 23
3.3.2.1 石墨烯塗料之配製 23
3.3.2.2 氮摻雜石墨烯塗料之配製 23
3.3.2.3 氮摻雜石墨烯/二氧化錳複合物塗料之配製 24
3.3.2.4 電極之製作 24
3.3.3 超級電容器元件 25
3.3.3.1 固態電解質之配製 25
3.3.3.2 元件之製作 25
3.4 樣品之鑑定與特性分析 25
3.4.1 場發射掃描式電子顯微鏡 25
3.4.2 球面像差修正掃描穿透式電子顯微鏡 27
3.4.3 能量散佈分析 27
3.4.4 霍式轉換紅外光譜 28
3.4.5 拉曼光譜 28
3.4.6 光電子能譜 28
3.4.7 X射線繞射圖形 29
3.4.8 電化學分析 30
3.4.8.1 交流阻抗頻譜法 30
3.4.8.2 循環伏安法 31
3.4.8.3 恆電流充放電法 32
第四章 結果與討論 35
4.1 表面形貌 35
4.2 微結構分析 35
4.3 傅立葉轉換紅外光譜 43
4.4 拉曼光譜 43
4.5 光電子能譜 44
4.6 X射線繞射圖形 49
4.7 電極之電化學特性分析 51
4.7 元件之電化學特性分析 67
4.8 循環穩定性測試 80
第五章 結論 85
參考文獻 86

表目次
表3-1 藥品列表 20
表3-2 儀器設備列表 21
表4-1 各電極之EIS模擬阻抗值 54
表4-2 由電極之CV量測結果計算出各項電容特性參數 56
表4-3 由電極GCD量測結果計算出各項電容特性參數 61
表4-4 各元件之EIS模擬阻抗值 67
表4-5 由元件CV量測結果計算出各項電容特性參數 72
表4-6 由元件GCD量測結果計算出各項電容特性參數 77
表4-7 3-NGM1/G1元件經彎曲測試所獲之各項電容特性參數 82

圖目次
圖1-1 常見的儲能裝置之電容量充放電功率特性示意圖 2
圖1-2 常見的氮摻雜石墨烯中氮原子的鍵結配置 2
圖2-1 電雙層電容器操作示意圖 7
圖2-2 擬電容之電化學反應示意圖 7
圖2-3 氮/磷共摻雜石墨烯之製備流程示意圖 8
圖2-4 以氮超摻雜三維石墨烯作為電極材料之對稱超級電容器之循環穩定性測 試 8
圖2-5 Mn3O4奈米點/氮摻雜石墨烯之製作流程示意圖 12
圖2-6 Ragone圖: 與其它文獻數據相比，GF//GF、MnO2@PANI//MnO2@PANI和GF//MnO2@PANI展現出更佳性能 12
圖2-7 三維二氧化錳片和活性碳分別作為正極和負極材料之可撓式非對稱超級電容器組裝示意圖 13
圖2-8 AC//δ-ACEP@MnO2非對稱超級電容器組裝示意圖 13
圖2-9 以RGO為正極材料，RGO/MnO2為負極材料，組裝成全固態非對稱可撓式超級電容器示意圖 15
圖2-10 以二維MnO2奈米片和電化學剝離石墨烯做成交叉指紋圖形之電極，組裝成全固態平面微型超級電容器示意圖 15
圖2-11 ANF/GO所製作之電極應用於可撓式超級電容器示意圖 16
圖2-12 以噴墨列印技術將GO-MnO2奈米複合物製作成圖案化電極，進而組裝成可撓式非對稱超級電容器之示意圖 16
圖2-13 以MnO2和RGO水凝膠膜分別製作正極和負極，BC/PAAS-Na2SO4為固態電解質，組裝成可撓式超級電容器示意圖 19
圖2-14 基於NGMn之可撓式固態非對稱超級電容器示意圖 19
圖 3-1 電極/元件製作流程圖 26
圖3-2 典型的Nyquist plot 26
圖3-3 超級電容器元件3-NGM1/G1進行不同程度之彎曲測試 34
圖4-1 SEM影像(倍率5K): (a) 氧化石墨，(b) G，(c) NG，(d) 1-NGM，(e) 2-NGM，(f) 3-NGM，(g) 4-NGM，和(h) 5-NGM 36
圖4-2 SEM影像(倍率10K): (a) 氧化石墨，(b) G，(c) NG，(d) 1-NGM，(e) 2-NGM，(f) 3-NGM，(g) 4-NGM，和(h) 5-NGM 37
圖4-3 SEM影像(倍率50K): (a) 氧化石墨，(b) G，(c) NG，(d) 1-NGM，(e) 2-NGM，(f) 3-NGM，(g) 4-NGM，和(h) 5-NGM 38
圖4-4 NG之EDS mapping: (a) C，(b) O，(c) N 39
圖4-5 2-NGM之EDS mapping: (a) C，(b) O，(c) N，(d) Mn 40
圖4-6 3-NGM之EDS mapping: (a) C，(b) O，(c) N，(d) Mn 41
圖4-7 TEM影像: (a) NG，(c) 2-NGM，(e) 3-NGM；HRTEM高解析原子影像: (b) NG，(d) 2-NGM，(f) 3-NGM 42
圖4-8 FTIR光譜: 氧化石墨、G、NG、x-NGM 45
圖4-9 拉曼光譜: (a) GO，G，NG，x-NGM；(b) 僅x-NGM 46
圖4-10 GO、G、NG、x-NGM之XPS能譜: (a) C 1s，(b) O 1s，(c) N 1s，(d) Mn 2p 48
圖4-11 氧化石墨之XRD圖形 50
圖4-12 G、NG、x-NGM之XRD圖形 50
圖4-13 21種電極之Nyquist plots 52
圖4-14 圖4-13中插圖(a)、(b)、(c)之放大圖，其中實線為模擬曲線 53
圖4-15 CV曲線: Gy、NGy和1-NGMy等電極 54
圖4-16 CV曲線: x-NGMy電極 55
圖4-17 由CV結果所繪之Ragone plot: Gy、NGy和x-NGMy等21種電極 55
圖4-18 GCD曲線: Gy、NGy和1-NGMy等電極 63
圖4-19 不同電流密度對比電容作圖: Gy、NGy和x-NGMy等21種電極 63
圖4-20 GCD曲線: 3-NGM1電極 64
圖4-21 由GCD結果所繪之Ragone plot: Gy、NGy和x-NGMy等21種電極 64
圖4-22 Nyquist plots: Gy//G1、NGy//G1和x-NGMy//G1等元件 65
圖4-23 圖4-22中插圖(a)、(b)、(c)之放大圖，其中實線為模擬曲線 66
圖4-24 CV曲線: Gy//G1、NGy//G1和1-NGMy//G1等元件 70
圖4-25　CV曲線: x-NGMy//G1元件 70
圖4-26 由CV結果所繪之Ragone plot: Gy//G1對稱元件，以及NGy//G1和x-NGMy//G1等非對稱元件 71
圖4-27 GCD曲線: Gy//G1、NGy//G1和1-NGMy//G1等元件 71
圖4-28 不同電流密度對比電容作圖: Gy//G1、NGy//G1和x-NGMy//G1等元件 76
圖4-29 GCD曲線: 3-NGM1//G1元件 76
圖4-30 由GCD結果所繪Ragone plot: Gy//G1、NGy//G1和x-NGMy//G1等元件 79
圖4-31 CV彎曲測試圖: 3-NGM1//G1元件 79
圖4-32 GCD彎曲測試圖: 3-NGM1//G1元件 83
圖4-33 GCD彎曲測試之不同次數比較圖: 3-NGM//G1元件 83
圖4-34 循環壽命圖: 3-NGM1//G1非對稱元件 84
圖4-35 Ragone plot: 3-NGM1//G1元件結果(1 A·g-1、3 A·g-1、5 A·g-1、847 A·g-1、 9 A·g-1電流密度下)與其他文獻比較圖 84

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