第五章 反應結果與討論
5.4 水分解反應的化學式平衡
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Table 5.5 The gas evolution and pH value with different concentration of NaI.
I
5mM Pt/SrTiO
3 Pt/WO
3 9.6 μmol/g Neosepta 15mM Pt/SrTiO
3 Pt/WO
3 12.5 μmol/g Neosepta 6.50 : 5.95 5.11 : 8.89 15mM Pt/SrTiO
3 Pt/WO
3 8.4 μmol/g Neosepta+Nafion 6.79 : 8.83 5.85 : 10.21 20mM Pt/SrTiO
3 Pt/WO
3 9.3 μmol/g Neosepta 25mM Pt/SrTiO
3 Pt/WO
3 5.3 μmol/g Neosepta 5.83 : 5.50 9.15 : 10.50
10mM TaON Pt/WO
3 5.0 μmol/g Neosepta
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第六章 結論
本實驗利用雙胞反應器加入 I-/IO3-離子傳輸媒介協助水分解反應，在產氫觸 媒主要使用的是溶凝膠法製備的 SrTiO3:Rh，而在產氧觸媒部分則使用商用的 WO3，且兩者皆以白金附載其表面作為共觸媒以抓取電子至觸媒表面。而本研究 相較其他研究不同的地方在於，兩步驟的水分解反應系統已經被研究多年，主要 使用的離子傳輸媒介有 Fe2+/Fe3+和本研究用的 I-/IO3-，而本研究不同的地方在於 將此兩步驟水分解反應(Z-scheme)應用在雙胞反應系統當中，其間並以陰離子交 換膜 Neosepta 作隔離，由於離子溶液為偏中性，在水分解反應下對反應效率並 沒有甚麼太大的影響，但若是在以後有機會將此系統應用在 CO2的還原反應，
由於 CO2溶於水呈酸性的緣故，中性的離子溶液相較於必須要維持酸性的離子 溶液來說就會有較顯著的優勢。
本實驗在 15mM 濃度下使用產氫觸媒溶凝膠法製備之 Pt/SrTiO3:Rh 搭配商用 觸媒 Pt/WO3作雙胞反應器水分解反應，在 8 小時得出14μmol 的氫氣產量，而在 氧氣氫氣比例的方面在 4 小時和 6 小時的時候接近 0.5，在 8 小時的時候則為 0.63，
此外在在固態熔融法製備的 Ru/SrTiO3:Rh 產氫觸媒搭配商用觸媒 Pt/WO3在 15mM 最佳濃度狀態下的反應在 8 小時有14μmol 的氫氣產量，在 10 小時則有 17.5μmol 的氫氣產量，在氧氫比方面，第 8 小時和第 10 小時分別為 0.55 和 0.48，
接近於水分解的氫氧化學計量比。
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個人小傳
政緯於民國 77 年 10 月 21 日在台北出生，家中成員連同父母與兩位姐姐共 五人，自小皆在台北長大，父母也都在台北工作，國小期間曾經經歷過搬家，故 由台北市立忠義國小轉學到台北市立河堤國小，國中就讀古亭國中，並於基測考 取台北市立成功高中，之後在大學指定科目考試中考取國立台灣大學化學工程學 系，大學期間所學及所見仍舊讓我印象深刻，也遺憾當初沒成更把握光陰好好學 習和與更多人交流，之後在台灣大學的研究所考試中進入台大化工所攻讀碩士學 位，在吳紀聖老師指導下進行雙反應器可見光催化水分解的相關研究。