基于鋅帽型鉬磷酸鹽配位聚合物的合成及電化學(xué)性質(zhì)研究
發(fā)布時(shí)間：2018-11-24 16:02
【摘要】：多金屬氧酸鹽作為一類擁有多樣結(jié)構(gòu)和優(yōu)異物理化學(xué)性質(zhì)的一類納米簇,由于其高的電荷密度,氧化還原性能以及通過修飾可實(shí)現(xiàn)功能化等特點(diǎn),在醫(yī)學(xué),生物學(xué),磁性,材料科學(xué)和催化等領(lǐng)域展現(xiàn)出有前景的應(yīng)用價(jià)值。目前,多酸的修飾化成為實(shí)現(xiàn)多酸功能化的主要途徑,其中帽式多酸的研究一直是極具吸引力的課題。基于鋅帽的多金屬氧酸鹽的研究還不太多見,關(guān)于其性質(zhì)研究的報(bào)道就更少見。因此本論文將目光聚集在基于鋅帽的磷鉬酸鹽的結(jié)構(gòu)和性能研究,在本文中首次實(shí)現(xiàn)了鋅帽取代的多酸與線形剛性雙功能有機(jī)配體直接相連,同時(shí)Zn-ε-Keggin單元作為典型的可變價(jià)金屬簇顯示出可逆的氧化還原活性,因此多酸基配位聚合物可應(yīng)用于鋰離子電池以及電解水產(chǎn)氫中。在本論文中采用常規(guī)水熱的合成方法,通過調(diào)節(jié)PH值,與不同的配體實(shí)現(xiàn)了對(duì)鋅帽型磷鉬酸鹽的修飾。兩例具有金剛石拓?fù)涞慕Y(jié)構(gòu)新穎、同構(gòu)的多酸基配位聚合物被成功合成。通過單晶X-射線衍射、IR、TG以及元素分析等表征手段研究了化合物的組成、結(jié)構(gòu)等。(TBA)3 [PMoV8MoVI4O38(OH)2Zn4(IN)2](NENU-506)(TBA)3 [PMoV8MoVI4O38(OH)2Zn4(PBA)2]·H2O(NENU-507)不同于傳統(tǒng)的多酸基配位聚合物,NENU-506和NENU-507展現(xiàn)出很好的熱穩(wěn)定性和化學(xué)穩(wěn)定性。二者可以在很寬的PH范圍(2-12)內(nèi)穩(wěn)定存在,證明了其對(duì)酸/堿水溶液的極好耐受性。在室溫下將二者在常規(guī)有機(jī)溶劑浸泡3天后,其PXRD顯示二者仍保持著晶體框架,證明其在常規(guī)溶劑中也具有很好的穩(wěn)定性。鑒于NENU-507優(yōu)異的化學(xué)和熱穩(wěn)定性,將其直接用作鋰離子電池的負(fù)極材料。研究表明,在鋰化/脫鋰循環(huán)期間,NENU-507能夠保持其三維剛性結(jié)構(gòu)。當(dāng)電流密度為100 mA g-1時(shí),NENU-507電極在100個(gè)循環(huán)后顯示出的可逆容量為640 mA h g-1。在相似的條件,利用四帽鋅取代的磷鉬酸與含羧酸的有機(jī)配體形成了化合物NENU-508,其分子式為:(TBA)5[PMoV8MoVI4O38(OH)2Zn4(NTB)Cl];與含氮的有機(jī)配體形成了化合物NENU-509,其分子式:(TBA)[PMoV8MoVI4O38(OH)2Zn4(BDMPX)2]·5H2O,并且對(duì)二者進(jìn)行了紅外、XRPD、熱重表征,他們具有較好的酸堿穩(wěn)定性。由于POM單元的氧化還原活性以及MOF的孔隙,使得其有望替代貴金屬催化劑,應(yīng)用于電解水產(chǎn)氫的研究。
[Abstract]:Polyoxometalates are a kind of nanoclusters with various structures and excellent physical and chemical properties. Due to their high charge density, redox properties and functionalization through modification, polyoxometalates are widely used in medicine, biology, magnetism, etc. Materials science and catalysis show promising application value. At present, the modification of polyacids is the main way to realize the functionalization of polyacids. Studies on zinc cap-based polyoxometalates have not been seen much, and reports on their properties are even rarer. Therefore, the structure and properties of phosphomolybdate based on zinc cap are studied in this paper. In this paper, the polyacid replaced by zinc cap is directly connected with linear rigid bifunctional organic ligands for the first time. At the same time, the Zn- 蔚-Keggin unit shows reversible redox activity as a typical variable valence metal cluster, so polyacid-base coordination polymers can be used in lithium ion batteries and electrolytic aquatic hydrogen. In this paper, the zinc cap phosphomolybdate was modified with different ligands by adjusting the PH value by the conventional hydrothermal synthesis method. Two examples with diamond topology have been successfully synthesized, with novel structure and isomorphic polyacid-group coordination polymer. The composition of the compounds was studied by means of X-ray diffraction, IR,TG and elemental analysis. The structure of. (TBA) _ 3 [PMoV8MoVI4O38 (OH) 2Zn4 (IN) _ 2] (NENU-506) (TBA) _ 3 [PMoV8MoVI4O38 (OH) 2Zn4 (PBA) _ 2] H _ 2O (NENU-507) is different from that of traditional polyacid-group coordination polymers. NENU-506 and NENU-507 show good thermal and chemical stability. They can exist stably in a wide range of PH (2-12), which proves their excellent tolerance to acid / alkaline water solution. After immersing them in conventional organic solvents at room temperature for 3 days, their PXRD showed that they still maintained the crystal frame, which proved that they also had good stability in conventional solvents. Due to its excellent chemical and thermal stability, NENU-507 is directly used as anode material for lithium ion batteries. The results show that NENU-507 can maintain its three dimensional rigid structure during lithiation / delithium cycle. When the current density is 100 mA g ~ (-1), the reversible capacity of the NENU-507 electrode is 640 mA h ~ (-1) after 100 cycles. Under similar conditions, the compound NENU-508, was formed by using the organic ligands containing carboxylic acids and substituted phosphomolybdic acid. The molecular formula of the compound is: (TBA) 5 [PMoV8MoVI4O38 (OH) 2Zn4 (NTB) Cl]. The compound NENU-509, was formed with nitrogen-containing organic ligands and its molecular formula: (TBA) [PMoV8MoVI4O38 (OH) 2Zn4 (BDMPX) _ 2] _ 5H _ 2O was obtained. They were characterized by IR and XRPD, thermogravimetry. They have good acid-base stability. Because of the redox activity of POM unit and the pore of MOF, it is expected to replace the noble metal catalyst and be used in the study of electrolytic hydrogen in aquatic products.
【學(xué)位授予單位】：東北師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O641.4
本文編號(hào)：2354307
[Abstract]:Polyoxometalates are a kind of nanoclusters with various structures and excellent physical and chemical properties. Due to their high charge density, redox properties and functionalization through modification, polyoxometalates are widely used in medicine, biology, magnetism, etc. Materials science and catalysis show promising application value. At present, the modification of polyacids is the main way to realize the functionalization of polyacids. Studies on zinc cap-based polyoxometalates have not been seen much, and reports on their properties are even rarer. Therefore, the structure and properties of phosphomolybdate based on zinc cap are studied in this paper. In this paper, the polyacid replaced by zinc cap is directly connected with linear rigid bifunctional organic ligands for the first time. At the same time, the Zn- 蔚-Keggin unit shows reversible redox activity as a typical variable valence metal cluster, so polyacid-base coordination polymers can be used in lithium ion batteries and electrolytic aquatic hydrogen. In this paper, the zinc cap phosphomolybdate was modified with different ligands by adjusting the PH value by the conventional hydrothermal synthesis method. Two examples with diamond topology have been successfully synthesized, with novel structure and isomorphic polyacid-group coordination polymer. The composition of the compounds was studied by means of X-ray diffraction, IR,TG and elemental analysis. The structure of. (TBA) _ 3 [PMoV8MoVI4O38 (OH) 2Zn4 (IN) _ 2] (NENU-506) (TBA) _ 3 [PMoV8MoVI4O38 (OH) 2Zn4 (PBA) _ 2] H _ 2O (NENU-507) is different from that of traditional polyacid-group coordination polymers. NENU-506 and NENU-507 show good thermal and chemical stability. They can exist stably in a wide range of PH (2-12), which proves their excellent tolerance to acid / alkaline water solution. After immersing them in conventional organic solvents at room temperature for 3 days, their PXRD showed that they still maintained the crystal frame, which proved that they also had good stability in conventional solvents. Due to its excellent chemical and thermal stability, NENU-507 is directly used as anode material for lithium ion batteries. The results show that NENU-507 can maintain its three dimensional rigid structure during lithiation / delithium cycle. When the current density is 100 mA g ~ (-1), the reversible capacity of the NENU-507 electrode is 640 mA h ~ (-1) after 100 cycles. Under similar conditions, the compound NENU-508, was formed by using the organic ligands containing carboxylic acids and substituted phosphomolybdic acid. The molecular formula of the compound is: (TBA) 5 [PMoV8MoVI4O38 (OH) 2Zn4 (NTB) Cl]. The compound NENU-509, was formed with nitrogen-containing organic ligands and its molecular formula: (TBA) [PMoV8MoVI4O38 (OH) 2Zn4 (BDMPX) _ 2] _ 5H _ 2O was obtained. They were characterized by IR and XRPD, thermogravimetry. They have good acid-base stability. Because of the redox activity of POM unit and the pore of MOF, it is expected to replace the noble metal catalyst and be used in the study of electrolytic hydrogen in aquatic products.
【學(xué)位授予單位】：東北師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O641.4
【參考文獻(xiàn)】
相關(guān)期刊論文 前1條
1 劉婭;徐峰;;世界氫能與氫經(jīng)濟(jì)的發(fā)展概況及不同認(rèn)識(shí)[J];世界科技研究與發(fā)展;2006年01期
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