釕聯吡啶錯合物在水中催化碘離子的反應
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2020
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論文研究中合成出一系列配位基的釕錯合物，[Ru(dmbpy)3](PF6)2、[Ru2(bpy)2(dmbpy)](PF6)2、[Ru(bpy)3](PF6)2、[Ru(dmbpy)2(deeb)](PF6)2及 [Ru(bpy)2(deeb)](PF6)2，由配位基的改變來調整其還原電位，且都以 X-ray、 NMR、ESI-MS 來鑑定其結構及純度。
錯合物皆使用電子吸收光譜、冷光光譜，測量其基本光化學性質，再以瞬時吸收光譜測得生命期。
為了討論錯合物的還原電位與淬熄效率的關係，使用循環伏安法，得到錯合物氧化還原電位，再利用冷光光譜所得激發態的位能 (E00) 計算出電子傳遞的驅動力。
五種錯合物照光激發後，與氧化淬熄劑 [(Co(NH3)5Cl]Cl2在水相進行雙分子淬熄反應，經由Stern–Volmer equation得知淬熄速率常數 kq 介於 1.25 x 109 M-1s-1 和 5.01 x 107 M-1s-1 之間，對應於淬熄反應的驅動力 -ΔGET 為 1.63 到1.11 eV，有正相關性。
淬熄後得到三價釕錯合物，再與碘離子反應，由瞬時吸收光譜量測出電子傳遞速率常數 kET(I) ，為 7.13 x 109 M-1s-1 ，最高到 1.14 x 1010 M-1s-1，相對反應驅動力 -ΔGET(I) 為 0.32 至 0.57 eV。
最後的光化學產物為 triiodide 及 iodine，利用水和正己烷不互溶且 iodine 難溶於水的性質，可以把 iodine 從正己烷萃取出，並用電子吸收光譜鑑定其生成 (在正己烷中，iodine吸收峰為521nm)，計算出其濃度，再進一步可以算出釕錯合物的催化效率 Turnover number。
太陽能是取之不盡的，而本論文由太陽能取得「原本需消耗能量」才能得到的能量: I2 (Iodine)。
In the paper, a series of ligand-based ruthenium metal complexes were synthesized, [Ru(dmbpy)3](PF6)2、[Ru(bpy)2(dmbpy)](PF6)2、[Ru(bpy)3](PF6)2、[Ru(dmbpy)2(deeb)](PF6)2 and [Ru(bpy)2(deeb)](PF6)2. The reduction potential is adjusted by the change of the ligand, and both The structure and purity were identified by X-ray, NMR, and ESI-MS. The complexes were measured by electron absorption spectroscopy and luminescence spectroscopy, and their photochemical properties were measured. The lifetime was measured by pulsed laser spectroscopy. In order to discuss the relationship between the reduction potential of the complex and the quenching efficiency, cyclic voltammetry was used to obtain the redox potential of the complex, and the driving force of electron transfer was calculated by using the potential energy (E00) of the excited state obtained by the luminescence spectroscopy. After the six complexes were excited by light, they were subjected to bimolecular quenching reaction with the oxidation quencher [(Co(NH3)5Cl]Cl2 in the aqueous solution. The quenching rate constant kq was calculated via the Stern–Volmer equation. Between 1.25 x 109 M-1s-1 and 5.01 x 107 M-1s-1, the driving force corresponding to the quenching reaction - ΔGET is 1.63 to 1.11 eV, which has a positive correlation. After quenching, the trivalent metal complex was obtained and reacted with iodide ions to measure the electron transfer rate constant kET(I) through the transient absorption spectroscopy, which is 7.13 x 109 M-1s-1, up to 1.14 x 1010 M-1s-1. The relative reaction driving force - ΔGET(I) is 0.32 to 0.57 eV. The final photochemical products are triiodide and iodine. The water and n-hexane are immiscible and the iodine is insoluble in water. The iodine can be extracted from n-hexane and identified by electron absorption spectroscopy (in hexane, iodine absorption peak is 521 nm), the concentration is calculated, and the turnover number of the ruthenium complexes can be calculated. Solar energy is inexhaustible, and this paper can obtain the energy through solar energy：I2 (Iodine).
In the paper, a series of ligand-based ruthenium metal complexes were synthesized, [Ru(dmbpy)3](PF6)2、[Ru(bpy)2(dmbpy)](PF6)2、[Ru(bpy)3](PF6)2、[Ru(dmbpy)2(deeb)](PF6)2 and [Ru(bpy)2(deeb)](PF6)2. The reduction potential is adjusted by the change of the ligand, and both The structure and purity were identified by X-ray, NMR, and ESI-MS. The complexes were measured by electron absorption spectroscopy and luminescence spectroscopy, and their photochemical properties were measured. The lifetime was measured by pulsed laser spectroscopy. In order to discuss the relationship between the reduction potential of the complex and the quenching efficiency, cyclic voltammetry was used to obtain the redox potential of the complex, and the driving force of electron transfer was calculated by using the potential energy (E00) of the excited state obtained by the luminescence spectroscopy. After the six complexes were excited by light, they were subjected to bimolecular quenching reaction with the oxidation quencher [(Co(NH3)5Cl]Cl2 in the aqueous solution. The quenching rate constant kq was calculated via the Stern–Volmer equation. Between 1.25 x 109 M-1s-1 and 5.01 x 107 M-1s-1, the driving force corresponding to the quenching reaction - ΔGET is 1.63 to 1.11 eV, which has a positive correlation. After quenching, the trivalent metal complex was obtained and reacted with iodide ions to measure the electron transfer rate constant kET(I) through the transient absorption spectroscopy, which is 7.13 x 109 M-1s-1, up to 1.14 x 1010 M-1s-1. The relative reaction driving force - ΔGET(I) is 0.32 to 0.57 eV. The final photochemical products are triiodide and iodine. The water and n-hexane are immiscible and the iodine is insoluble in water. The iodine can be extracted from n-hexane and identified by electron absorption spectroscopy (in hexane, iodine absorption peak is 521 nm), the concentration is calculated, and the turnover number of the ruthenium complexes can be calculated. Solar energy is inexhaustible, and this paper can obtain the energy through solar energy：I2 (Iodine).
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Keywords
釕金屬錯合物, 碘離子, 水溶液, ruthenium(II) bipyridine-type complexes, iodide, aqueous solution