氨不僅能作為化學原料和植物肥料，還是一種可提供高能量密度的無碳能源載體。現今，許多研究致力於尋找可再生資源的氨合成技術。其中，在常溫常壓環境下，通過電催化氮還原技術合成氨，是目前工業採用的高能源消耗及較低延續性的哈柏製氨法的替代方法。
本研究使用鐵和鈷共摻雜二硫化鉬生長在碳布上作為電催化劑，實現了在弱酸性電解液中的電催化氮還原，實驗結果顯示，相較於純二硫化鉬，適當摻雜濃度的鐵鈷共摻雜二硫化鉬，在各個電壓下的氨產率皆大幅度上升，在電位-0.55 V，達到3.27 µg h−1 cm−2之氨產率，超過純二硫化鉬、鐵摻雜二硫化鉬及鈷摻雜二硫化鉬的氨產率，分別為191%、176%及116%；法拉第效率也有明顯提升，在電位-0.35 V，達到6.28%之法拉第效率，分別為純二硫化鉬、鐵摻雜二硫化鉬及鈷摻雜二硫化鉬的217%、186%及132%之法拉第效率，顯示提高鐵摻雜濃度並加入少量的鈷摻雜，可以提升材料的催化活性。而增強的電催化產氨性能可歸因於鐵和鈷摻雜原子的協同作用，不僅引入活性位點，增加材料本質活性，還促進了材料的電荷轉移。
此外，密度泛函理論計算結果顯示鐵鈷共摻雜二硫化鉬的反應最佳路徑為末端途徑，且其電位決定步驟之自由能障僅0.54 eV，比純二硫化鉬之自由能障1.13 eV低許多，表示鐵鈷共摻雜二硫化鉬能有更好的催化活性；而巴德電荷分析結果顯示鐵鈷共摻雜可促進電荷轉移，減弱鉬原子對反應中間產物之吸附能力，使氮還原反應優先發生在作為活化位置的鐵原子，綜合上述，適量的鐵鈷共摻雜濃度能使二硫化鉬的催化活性提升。

Ammonia is not only essential to life as a chemical feedstock and fertilizers but also considered as a carbon-free energy carrier that offers high energy density. Nowadays, many efforts have been devoted to searching renewable-energy-based NH3 synthesis techniques. In particular, NH3 synthesis by the electrocatalytic N2 reduction reaction (NRR) under ambient conditions is a promising alternative way to the currently employed energy-intensive and non-sustainable Haber-Bosch process.
In this thesis, we demonstrated that the NRR could be achieved by using Fe and Co co-doping MoS2 nanosheets supported on carbon cloth that served as an electrocatalyst. At optimal doping concentration, Fe and Co co-doping MoS2 exhibited an ammonia yield rate of 3.27 µg h−1 cm−2 at −0.55 V versus RHE, which reached higher performance than that of undoped MoS2, Fe-doped MoS2 and Co-doped MoS2 samples by 191%, 176% and 116%, respectively, and a FE of 6.28% at -0.35 V versus RHE, exceeding that of undoped MoS2, Fe-doped MoS2 and Co-doped MoS2 samples by 217%, 186% and 132%, respectively. The enhanced NRR performance can be attributed to the synergistic effects of Fe and Co dopants which induce the active sites, increase intrinsic activity, and promote the charge transfer.
Additionally, density functional theory calculations reveal that the preferred reaction pathway of FeCo-MoS2 electrocatalyst is distal pathway and its potential-determining step has a lower energy barrier（0.54 eV）than that of undoped MoS2（1.13 eV）which indicates FeCo-MoS2 possesses better electrocatalytic activity. Besides, the Bader analysis shows that Fe and Co dopants enable electron transfer and thus optimize the free energies of reaction intermediates. Therefore, Fe and Co were determined to be effective dopants for boosting the NRR activity of MoS2 catalyst.

摘要 I
Abstract II
致謝 III
目錄 IV
圖目錄 VII
表目錄 XII
第一章 緒論與文獻探討 1
1.1. 氨能源 1
1.2. 氨合成方法 3
1.2.1. 自然固氮 4
1.2.2. 哈柏法製氨 5
1.2.3. 光催化產氨 6
1.2.4. 電催化產氨 9
1.3. 電催化氮還原產氨反應 11
1.3.1. 反應機制 11
1.3.2. 反應路徑 12
1.3.3. 氮還原表現指標 14
1.3.4. 密度泛函理論（Density functional theory, DFT）計算 15
1.4. 氨氣產量之定量測定方法 17
1.4.1. 分光光度法（Spectrophotometry） 17
1.4.2. 離子層析法（Ion chromatography, IC） 18
1.4.3. 離子選擇電極法（Ion-selective electrode, ISE） 19
1.4.4. 核磁共振光譜法（Nuclear magnetic resonance, NMR） 19
1.5. 催化劑的發展與設計 20
1.5.1. 二維材料 21
1.5.2. 二硫化鉬材料 22
1.5.2.1. 二硫化鉬基本性質 22
1.5.2.2. 二硫化鉬製備方法 23
1.5.2.3. 二硫化鉬作為電催化產氨反應的催化劑 26
1.5.3. 摻雜對催化的影響 28
1.5.3.1. 鐵摻雜原子 29
1.5.3.2. 鈷摻雜原子 30
1.6. 研究動機 32
第二章 實驗方法與儀器 33
2.1. 實驗架構 33
2.2. 電催化劑之製備流程 34
2.2.1. 二硫化鉬/碳布複合材料（MoS2/CC）之合成 34
2.2.2. 鐵摻雜二硫化鉬/碳布複合材料（Fe-MoS2/CC）之合成 34
2.2.3. 鈷摻雜二硫化鉬/碳布複合材料（Co-MoS2/CC）之合成 34
2.2.4. 鐵鈷摻雜二硫化鉬/碳布複合材料（FeCo-MoS2/CC）之合成 35
2.2.5. 工作電極製備 36
2.3. 電化學分析之系統架設 37
2.3.1. 電解池 37
2.3.2. 離子交換膜 38
2.3.3. 氣體 38
2.4. 靛酚藍分光光度法測定氨氣產量 39
2.5. 實驗儀器介紹 40
2.5.1. 掃描式電子顯微鏡（Scanning Electron Microscope, SEM） 40
2.5.2. 顯微拉曼散射光譜儀（Micro-Raman Spectroscope） 41
2.5.3. X光繞射分析儀（X-Ray Diffractometer, XRD） 42
2.5.4. 穿透式電子顯微鏡（Transmission Electron Microscope, TEM） 43
2.5.5. 能量色散X光光譜儀（Energy-dispersive X-ray Spectroscope, EDS） 45
2.5.6. X光光電子能譜儀（X-ray Photoelectron Spectroscope, XPS） 46
2.5.7. 紫外光-可見光吸收光譜儀（UV-Visible Spectroscope） 47
2.5.8. 電化學分析儀（Electrochemical analyzer） 48
第三章 結果與討論 49
3.1. 結構鑑定 49
3.1.1. SEM影像分析 49
3.1.2. XRD分析 52
3.1.3. Raman光譜分析 53
3.1.4. TEM分析 55
3.1.5. XPS能譜分析 59
3.2. 電催化表現分析 64
3.2.1. LSV分析 64
3.2.2. CA分析 68
3.2.3. 氨氣產量測定分析 72
3.2.4. 氮還原性能分析 75
3.3. DFT理論計算 79
3.3.1. 計算方法 79
3.3.2. 優化幾何結構 80
3.3.3. 反應機構自由能圖 82
3.3.4. 巴德電荷分析（Bader charge analysis） 85
3.4. 產氨比較 87
第四章 結論 88
第五章 未來展望 89
參考文獻 90

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