本文選題：氨硼烷 + 質(zhì)子響應(yīng)型配合物�。� 參考：《大連理工大學(xué)》2015年碩士論文

【摘要】：隨著當(dāng)前化石燃料的急劇消耗及能源需求的日益增加,探尋新的替代能源迫在眉睫。氫能作為高效清潔的綠色新能源備受關(guān)注,而安全高效的儲運氫氣又是推廣氫能應(yīng)用、發(fā)展氫經(jīng)濟(jì)的關(guān)鍵。氨硼烷具有超高的含氫密度(19.6 wt%),成為目前熱門研究的儲氫材料。在其多種放氫方式中,催化氨硼烷水解制氫具有放氫速率快,放氫量大,反應(yīng)溫度低且反應(yīng)不產(chǎn)生有毒副產(chǎn)物等優(yōu)勢。多相催化氨硼烷水解制氫已有相當(dāng)程度的研究,然而放氫速率距實際應(yīng)用仍有差距；且催化劑用量大、回收困難,失去多相催化的優(yōu)勢。與多相催化相比,均相催化的反應(yīng)活性中心分散均勻,催化效率及選擇性高。但是均相催化的氨硼烷水解制氫卻鮮有報道,其中的一個重要原因是缺少易溶于水的穩(wěn)定的催化劑。本文針對目前存在的問題,合成了一系列的水溶性配合物,并用于均相催化氨硼烷水解制氫反應(yīng)。對配合物的催化活性及催化反應(yīng)機(jī)理進(jìn)行了探索性研究。1)合成了一系列含羥基的聯(lián)吡啶、聯(lián)嘧啶雙齒配體,并與[Cp*Ir(OH2)3]SO4或[Cp*IrCl2]2反應(yīng)合成了相應(yīng)的四種質(zhì)子響應(yīng)型銥配合物。由于羥基官能團(tuán)的存在,該類配合物展示出良好的水溶性和穩(wěn)定性。2)將該系列質(zhì)子響應(yīng)型配合物應(yīng)用于均相催化氨硼烷水解制氫的反應(yīng)中,并考察了溫度、催化劑量、pH值以及氨硼烷濃度對催化反應(yīng)的影響。綜合比較,最終確定的最優(yōu)反應(yīng)條件為：反應(yīng)溫度65℃,催化劑用量1 μmol,溶液pH為9,氨硼烷濃度為0.1 mol/L。3)本文還研究了壓力因素對反應(yīng)的影響。使催化水解放氫反應(yīng)在密閉的反應(yīng)釜中進(jìn)行。最終發(fā)現(xiàn)即使在壓力條件下,該類催化劑仍能催化氨硼烷水解,并完全釋放3當(dāng)量的氫氣。3小時內(nèi)所有氨硼烷底物(3.6 mmol)都完全轉(zhuǎn)化,TON值達(dá)到3600。4)在最優(yōu)反應(yīng)條件下,篩選出催化效果最好的催化劑為[Cp*Ir(6,6'-(OH)2-bpy)-(OH2)]S04。該催化劑于最優(yōu)反應(yīng)條件下,可在0.7 h內(nèi)完全釋放3當(dāng)量的氫氣,初始轉(zhuǎn)化頻率(TOF值)達(dá)5496 h-1(最初5 min)。根據(jù)實驗結(jié)果及前人的研究,我們提出了設(shè)想的氨硼烷水解制氫的催化機(jī)理。在水分子參與下,質(zhì)子響應(yīng)型配合物上的羥基官能團(tuán)與金屬中心協(xié)調(diào)作用催化氨硼烷脫氫。
[Abstract]:With the rapid consumption of fossil fuels and the increasing demand for energy, it is urgent to explore new alternative energy sources. Hydrogen energy, as a new green energy source with high efficiency and cleanliness, has attracted much attention, and safe and efficient storage and transportation of hydrogen is the key to promote the application of hydrogen energy and develop hydrogen economy. Aminoborane, with a high hydrogen density of 19.6 wtcm, has become a hot research material for hydrogen storage. The catalytic hydrolysis of ammonioborane to produce hydrogen has the advantages of fast hydrogen release rate, large amount of hydrogen release, low reaction temperature and no toxic by-products. Heterogeneous catalytic hydrolysis of ammonium-borane to produce hydrogen has been studied to a considerable extent, but the rate of hydrogen release is still far from the practical application, and the amount of catalyst is large, the recovery is difficult, and the advantage of heterogeneous catalysis is lost. Compared with heterogeneous catalysis, the active centers of homogeneous catalytic reaction are uniform, and the catalytic efficiency and selectivity are higher. However, homogeneous catalytic hydrolysis of aminoborane to produce hydrogen is rarely reported, and one of the important reasons is the lack of stable catalyst which is easily soluble in water. In this paper, a series of water-soluble complexes were synthesized in allusion to the existing problems, and were used for homogeneous catalytic hydrolysis of aminoborane to produce hydrogen. A series of hydroxy bipyridine and bipyrimidine didentate ligands were synthesized and reacted with [Cp*Ir(OH2)3] SO4 or [Cp*IrCl2] 2 to synthesize four proton responsive iridium complexes. Due to the existence of hydroxyl functional groups, the complexes exhibit good water solubility and stability. 2) the series of proton responsive complexes were used in homogeneous catalytic hydrolysis of aminoborane to produce hydrogen, and the temperature was investigated. The effect of the amount of catalyst pH and the concentration of ammonia borane on the catalytic reaction. The optimum reaction conditions were as follows: reaction temperature 65 鈩，

本文編號：1974311