「永續發展」一詞近年來備受注目，如何與大自然和平相處的同時又能繼續推動人類文明進步儼然已成為各國的發展目標。替代性能源的發展開花結果，只為了早日達成碳中和的目標。綠色氫能是許多替代性能源中極具發展潛力的能源之一，透過電解水陰極的析氫反應(Hydrogen Evolution Reaction, HER)能夠解決再生能源間歇性發電的問題，將電能轉換成化學能的形式存儲於高能量密度的氫氣作為能源載體，再以燃料電池方式發電。質子交換膜電解水器(Proton Exchange Membrane Water Electrolyzer, PEMWE)擁有體積小、高產氫效率和方便分離產物的優點，成為商業化綠色產氫的解決方案之一。
PEMWE最大的缺點為設置成本高昂，除了硬體設備的成本外，長時間操作下需定期更換陰陽極觸媒材料以維持高效率更是一筆可觀的花費。不同於鹼性和中性電解水條件，PEMWE的陽極析氧反應(Oxygen Evolution Reaction, OER)之操作環境十分嚴苛(酸性、高氧化電位)，在過去數十年的文獻中僅有貴金屬觸媒(二氧化銥、二氧化釕)才有比較優秀且穩定的催化表現，且析氧反應牽涉到四個電子轉移，使其為水分解速率決定步驟。因此，本研究中以PEMWE為最終的水分解產氫測試平台，開發出在液相酸性條件下可長效穩定催化析氧反應的非貴金屬陽極觸媒材料，並透過膜電極模組(Membrane Electrode Assembly, MEA)的組裝將觸媒材料轉移至PEMWE平台上，進行相關水分解催化研究。
本研究中開發出以摻氟氧化錫為核、四氧化三鈷為殼之材料FTO@Co3O4，其於0.5 M硫酸中，催化OER達成電流密度10 mA cm-2之過電位為511 mV，並且在電流密度10 mA cm-2操作21.5小時，操作電位僅上升2%。將FTO@Co3O4噴塗於質子交換膜表面，在PEMWE測試平台上作為陽極觸媒(3 mg cm-2)，陰極材料使用商用鉑碳觸媒(0.2 mgPtC cm-2)，在室溫下電位為2 V時達成的電流密度為0.205 A cm-2，並且在電流密度10 mA cm-2下操作21.5小時，操作電位僅上升5.2%。在70 oC下電位為2 V時達成的電流密度為0.258 A cm-2，並且在電流密度10 mA cm-2下操作50小時，操作電位僅上升5.2%。以非貴金屬元素作為PEMWE陽極觸媒而言，實屬優異。

Sustainable developments have highly attracted a great deal of attention in recent years. To meet the goal of carbon neutrality, “green hydrogen” becomes one of the most promising alternative energy candidates because of its high energy densities. Through electrochemical water splitting, one can covert electric powers to chemical energies with the “hydrogen evolution reaction (HER)” to resolve the unreliability issue of renewable energies. One can then generate the electric powers by using hydrogen fuel cells. Proton exchange membrane water electrolyzers(PEMWE), possessing advantages of compact size, high hydrogen production efficiency and convenience of hydrogen separation become one of the promising routes for green hydrogen production.
The main disadvantage of PEMWE is the high cost of installation and the periodical replacement of the noble metal based electrocatalyst. Oxygen evolution reaction (OER) involves a four-electron transfer and thus is the bottleneck of electrochemical water splitting. Different from alkaline or neutral water splitting, the operation condition of OER in PEMWE is harsh because of the strong acidity and high oxidation potential involved. Conventionally, only noble metal-based catalysts like iridium and ruthenium oxide can survive and show great OER electrocatalytic performance in past research. In this study, we aim to develop a non-noble metal-based catalyst which can stably catalyze the OER in acidic electrolytes. Furthermore, through the membrane electrode assembly technique, we apply the catalyst to a PEMWE platform for water splitting.
We successfully develop a core-shell nanostructured material composed of F-doped tin oxide as core, and cobalt oxide as shell (FTO@Co3O4). This catalyst achieves an OER overpotential of 511 mV at 10 mA cm-2 in 0.5 M sulfuric acid, and the operation potential increases by 2% after 21.5 hours operation at 10 mA cm-2. In the PEMWE platform, we use a catalyst coated membrane (CCM) method to spray-coating FTO@Co3O4 on to the proton exchange membrane as the anode and Pt/C as the cathode. It shows superior performances as compared with other non-noble metal catalysts at room temperature, with a current density of 0.205 A cm-2 achieved at 2V, and a 5.2% increase in cell voltage after 21.5 hours operation under 10 mA cm-2. At 70oC, it has current density of 0.258 A cm-2 achieved at 2V, and a 5.2% increase in cell voltage after 50 hours operation under 10 mA cm-2.

摘要 2
Abstract 4
致謝 6
圖目錄 9
表目錄 12
第一章 緒論 13
1.1前言 13
1.2電催化分解水原理 14
1.3反應過電位 15
1.4三極式電化學量測系統 16
1.4.1電解質 17
1.4.2參考電極 17
1.4.3對電極 19
1.5質子交換膜水電解器 19
1.5.1薄膜電極組 20
1.6常見用於質子交換膜水電解器之觸媒 21
1.6.1陰極材料 22
1.6.2陽極材料 22
1.7研究動機 23
第二章 文獻回顧 24
2.1鈷及其衍生物於質子交換膜水電解器陽極觸媒之應用 25
2.2二氧化錳於質子交換膜水電解器陽極觸媒之應用 31
第三章 實驗方法 36
3.1實驗藥品 36
3.2實驗器材 38
3.3材料性質分析儀器 39
3.4實驗方法及步驟 41
3.4.1 摻氟氧化錫/四氧化三鈷複合(FTO@Co3O4)奈米材料 41
3.4.2四氧化三鈷/摻氟氧化錫複合(Co3O4@FTO)奈米材料 42
3.4.3製作OER三極式電化學量測電極 43
3.4.4膜電極模組的製作 43
3.5電化學表現量測 44
3.5.1 OER過電位量測 44
3.5.2 長效性測試 45
3.5.3 電化學阻抗頻譜分析法 45
3.5.4 質子交換膜水電解器量測 45
第四章 結果與討論 47
4.1四氧化三鈷與摻氟氧化錫複合材料之材料分析 47
4.1.1 FTO@Co3O4材料分析 47
4.1.2 Co3O4@FTO材料分析 55
4.2四氧化三鈷與摻氟氧化錫複合材料之電化學性質分析 61
4.2.1四氧化三鈷與摻氟氧化錫複合材料OER電化學表現 62
4.2.2四氧化三鈷與摻氟氧化錫複合材料電化學交流阻抗測試 63
4.2.3四氧化三鈷與摻氟氧化錫複合材料OER長效性測試 65
4.3 四氧化三鈷與摻氟氧化錫複合材料組成質子交換膜水電解器 72
第五章 結論 81
參考資料 82

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