• 沒有找到結果。

利用 in situ FT-IR 方式來偵測乙醇電氧化反應來推斷合金觸媒的反應機構為 當今常用的研究方法,除了本文使用循環伏安法以掃描圈數同時偵測之外,還可 以利用計時安培法固定某一電位來做及時偵測,除了可以讓我們得知當下電位電 極表面產生的中間產物之外,還能以各個電位產生的中間產物綜合起來更精確的 推斷金屬的反應途徑。本研究中的 in situ FT-IR 還是無法看到 CO2(2325 cm-1)以 及其他更微弱地的官能基峰值變化,未來在實驗技術中改良後應可看到更細微的 變化,對於我們研究金屬對乙醇電氧化的反應機構將會更有幫助。

本實驗延續前面的研究,以鹼性 KOH 做為電解質,而在乙醇燃料電池的研究 中陽極大多是以酸性做為電解質(因為和室溫環境相同)研究,未來可以朝酸性溶 液來做研究,即使在酸性下大多數的金屬沒有活性[42],但只要將金屬參入 Pt,

以合金的方式來研究即可突破此一限制。

目前透過 FT-IR 以及 GC 等方式,我們大可歸類以乙二醇-硼酸還原法的合金 Pt3Rh、Pt3Ru,是走斷裂 C-C 鍵的 C1 路徑,而 Pt3Au、Pt3Ag 是走產生乙酸的 C2 路徑。這些合金以 Pt 做比較在穩定度、抗毒化程度以及電流密度上皆比 Pt 金屬來的好。未來也可嘗試合成三元材的合金觸媒,改善 CO 在電極表面上的毒 化現象或是更容易再乙醇氧化時斷裂其 C-C 鍵,開發更高效能而且抗毒化能力 更好的金屬觸媒,來提升乙醇燃料電時的效率。

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