4.1 甲醇氧化反應計算結論
Pt 與 Pd 所走路徑不太一致，Pt 傾向斷 O-H 鍵，所走的路徑為 CH3OH
CH3OCH2OCHOCO，而 Pd 傾向斷 C-H 鍵，所走的路徑為 CH3OH
CH2OH CH2O CHOCO 從脫氫路徑上分析，雖然兩者的路徑略有不同，但 皆會形成 CHO。而我們分別從 CH2O/CHO/CO 去討論氧化反應，探討氧化成 CH2OOH/CHOOH/COOH 的活化能大小，進而分析所走的路徑。從純金屬表面 的甲醇氧化反應我們發現 Pt 容易生成 CO，造成表面毒化問題；而 Pd 則易形成 CHOOH，利用這個特性我們討論了不同 Pt 與 Pd 比例混成合金，加入 Pd 去對 Pt 表面改性，藉由合金來降低活化能，提昇催化活性，藉此幫助反應進行。從 計算結果知道合金的活化能會降低，可以降低 CO 毒化問題，提升穩定度。
圖 4.1-1 甲醇路徑分析示意圖
藉由加入 Pd，我們可以發現反應路徑有所改變， Pt1Pd1的催化活性效果最好，
可以有效的降低 CHO 形成 CHOOH 的活化能，不容易形成 CO，相較於 Pt 表面 大大提升穩定度。且 CO 氧化活化能也是合金中最低的，表示 CO 較不容易殘留 表面。
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4.2 未來展望
█以 PtPd 合金，從計算的角度，去探討路徑。希望藉由中間產物的吸附能、反 應能，活化能等，從路徑去討論是否能說明實驗中常見的產物。
█探討其他雙金屬表面的 MOR 路徑，探討不同比例合金所得到的路徑上的差異 等等，期望能更完整的呈現實驗結果。
█從 MOR 的反應我們可以進一步去討論 EOR 反應的問題，在加入斷 C-C 鍵的 相關研究討論後，可以進一步分析 EOR 的反應
█考慮酸性與鹼性條件，藉此模擬不同環境下的 MOR 催化活性，並探討不同金 屬與合金在酸鹼環境下的活性。
█考慮加入電位進一步模擬真實電催化環境，探討 MOR 反應。
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