| 摘要: | 現今，氫氣已成為了最受矚目的能源載體，但目前利用電解方式所產生的氫氣所使用的電極為價格昂貴的白金電極，因此設計出一個具高活性及高穩定性的催化劑成為了現今的目標。
本論文主要藉由化學合成的方法模擬 [鐵鐵] 氫化酵素合成出一系列二鐵二硫催化劑，化合物 [{μ,κ2-3,6-(OC2H4N(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5]- (bdt = 1,2-benzenedithiolate, 2-) 與化合物 [{μ,κ2-3,6-(OC2H4N(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)] (3) 皆經過傅立葉轉換紅外線光譜 (FTIR)、核磁共振光譜 (NMR)、質譜 (MS) 以及元素分析 (EA) 鑑定，並透過X-ray繞射分析加以證實其固態結構。在反應性方面，本文描述了化合物2- 及化合物3在不同溶劑及不同強度的酸源中，具有多種的質子化反應路徑，目前發現化合物2 及化合物3最多可分別有六個及四個不同的質子化產物，藉此可試著模擬生物體中，[鐵鐵] 氫化酵素的質子化過程，同時也對兩者進行產氫催化速率 (kcat) 的比較。
除此之外，響應綠色化學與永續發展的理念，在此亦合成出含有四級胺的化合物 [{μ,κ2-3,6-(OC2H4N(CH3)3)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)]2+ (3(NMe)22+) 與化合物 [{μ,κ2-3,6-(OC2H4NH(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)]2+ (3(NH)22+)，經鑑定後，確認其為水溶性的化合物，並測量了兩者在水溶液中的電化學性質。
;Hydrogen is currently one of promising energy carriers. However, hydrogen production is mainly relied on electrolysis using high-cost Pt electrodes nowadays. Therefore, the development of a catalyst featuring higher activity and increased stability for hydrogen production is in urgent need.
Herein, a series of diiron dithiolate complexes are synthesized for the model study of the active site of [FeFe] hydrogenase. Complex [{μ,κ2-3,6-(OC2H4N(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5]- (bdt = 1,2-benzenedithiolate, 2) and [{μ,κ2-3,6-(OC2H4N(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)] (3) are characterized by Fourier-transform infrared spectroscopy (FTIR), NMR spectroscopy, mass spectrometry (MS), elemental analysis (EA) and X-ray crystallography. In our study, complexes 2- and 3 display distinct protonation pathways under various solution conditions in the presence of proton donors with different pKa values. The results show that up to 6 and 4 protonated species are derived from complexes 2 and 3, respectively, depending on reaction conditions. By doing so, we are able to simulate every potential protonation pathway in the enzymatic proton transfer process involving [FeFe] hydrogenases. In addition, we also estimate the kcat value for the hydrogen evolution reaction concerning individual protonated species.
Regarding green and sustainability of the title electrocatalytic systems, we also synthesize the following complexes containing quaternary amines moieties, [{μ,κ2-3,6-(OC2H4N(CH3)3)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)]2+ (3(NMe)22+) and [{μ,κ2-3,6-(OC2H4NH(CH3)2)2-bdt}(μ-PPh2)Fe2(CO)5(St-Me)]2+ (3(NH)22+). Both complexes display their water solubility. The electrochemical properties of these complexes in aqueous media are investigated. |
