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自从系列磷酸铝微孔晶体首次被报道以来, 空旷骨架磷酸盐化合物的合成取得了长足进展[1,2]. 其中, 空旷磷酸镓骨架化合物以其丰富的拓扑连接方式成为研究的热点之一[1,3,4]. 特别是向水热合成体系中引入氟离子, 导致了新颖微孔磷酸镓化合物的不断出现, 如磷酸镓-CLO[5], 磷酸镓MIL-31[6]等化合物. 目前, 合成实验表明, 乙烯胺类化合物(如二乙烯三胺)因其构象变化复杂, 可以诱导出多种新颖空旷骨架磷酸盐[7~9]. 由于氟离子可以同磷酸镓骨架中的镓原子配位, 进而改变骨架拓扑连接方式和电荷分布, 因此氟原子与二乙烯三胺协同作用可能获得新颖的无机骨架与导向剂的自组装模型. 相似文献
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过渡金属钴取代的钨镓杂多化合物的导电性*王力刘宗瑞周云山王恩波**(东北师范大学化学系长春130024关键词钨镓杂多配合物电导率固体电解质高质子导体中图分类号O641.4取代型杂多化合物的独特结构以及优异性能日益受到人们的重视[1]。我们在从事多酸研... 相似文献
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开放骨架结构金属磷酸盐不仅具有丰富的结构和组成多样性,而且在吸附、分离、和催化等方面具有潜在的应用前景[1 ̄3]。同磷酸铝一样[2,3],磷酸镓是开放骨架磷酸盐中一个重要的家族,其结构主要由交替的GaOn多面体(GaO4,GaO5及GaO6)和PO4四面体构成。目前,已有近百种磷酸镓在水热/溶剂热体系下成功的合成出来[4 ̄8],其中最著名的例子是具有二十员环超大孔磷酸镓Cloverite[5]。这些磷酸镓不仅具有结构上的新颖性,同时还具有丰富的组成计量比(Ga/P:1/2 ̄3/2)[9],它们的结构由多种次级结构单元(SBU)构成,拓扑相关性为定向设计提供了重要基… 相似文献
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以氯金酸和钛酸钠米管(NTA)为原料,柠檬酸三钠为稳定剂,硼氢化钠为还原剂,于室温条件下合成了一种金纳米颗粒-钛酸纳米管(GNPs-NTA)复合纳米材料;利用红外光谱仪、透射电镜、X射线粉末衍射仪等分析了产物的化学键合特征、微结构及相组成,并考察了产物对辣根过氧化酶(HRP)结构和生理活性的影响.结果表明,合成的纳米金颗粒粒径(平均5.3nm)分布窄,且均匀分布于钛酸纳米管表面.此外,HRP与GNPs-NTA复合纳米材料充分振荡混合后仍能保持其二级结构不变,有利于保持其生理活性. 相似文献
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The K2Ti4O9 whiskers were chosen for the catalyst carrier, TiO2/potassium titanate photocatalyst was prepared by Sol-gel method The product was characterated by X-ray diffraction and SEM. EDS shows that, the main peck included Ti, O, and K in potassium titanate whisker. The main peak of K disappeared and the peaks of Ti, O stayed after whisker was covered It directed that the surface of sample was covered by TiO2. XRD shows that diffraction peak appeared, which was corresponded to the peak of anatase TiO2. In the reaction device of photochemistry, using middle-pressure mercury lamp as illumination, rhodamine B as simulant pollutant, the photocatalytic performance of TiO2/potassium titanate was studied. Under the same conditions, the lower pH, the larger illuminance, the higher temperature, the greater aeration quantum and the lower initial concentration of rhodamine B, the higher decoloration rate was got. Under our experiment conditions: pH 6, the illuminance of 250W, the temperature of 313K, and the aeration quantum of 2.0L/min. When the concentration of rhodamine B was 8mg/L The photocatalyst of TiO2/potassium titanate was 0.01g/L. The decoloration rate of TiO2/potassium titanate dealt with the rhodamine B reach over 95% in 160min, and compare with TiO2, the decoloration rate of rhodamine B was improved 0.50-1.91 multiple. TiO2/potassium titanate can be used to treatment of dye wastewater. 相似文献
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Aluminum titanate was in-situ synthesized by using industrial waste-residue in the aluminum factory and TiO2 as the main raw materials and the influence of different reaction temperatures on the purity and microstructures of synthesized products were mainly discussed. The obtained Al2TiO5 was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and relevant analytical software. The results show that elevating the sintering temperature can increase the content of aluminum titanate; and at 1420 ℃, it reaches the highest in the synthesized ceramic. When the sintering temperature continues to increase, the produced aluminum titanate will decompose resulting in the drop of its content. Therefore, the optimum sintering temperature of in-situ synthesis of aluminum titanate is determined as 1420 ℃, at which the grains of aluminum titanate grow completely, the purity of aluminum titanate is 89.3wt%., the highest density is 2.75 g/cm^3, and the porosity is 9%. 相似文献
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以聚乙烯吡咯烷酮(PVP)为模板剂,钛酸四正丁酯(TBOT)为钛源,水热法制备纳米TiO2。采用XRD,SEM、TEM和UV-Vis DRS等测试手段对其形貌和结构进行表征。通过对甲基橙的光催化降解实验,探讨了焙烧温度、催化剂用量和溶液pH值对光催化性能的影响。结果表明,TiO2具有锐钛矿相,平均晶粒尺寸约为23.2 nm,TiO2颗粒呈片层状或由片层状堆积的疏松圆球形,经超声后即分散为八面体晶粒。550℃焙烧的样品,紫外光照3 h后,对甲基橙的降解率可达84.2%。相比普通水热法,采用模板剂法制得的TiO2吸收带发生红移,因而也具有较好的可见光催化活性。 相似文献
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采用低温共沉淀法, 借助调控合成反应体系的pH值, 制备了星形、花形和柱形3种不同形貌的钛酸锶钡(Ba0.85Sr0.15TiO3)粒子. 通过XRD, ICP, SEM及CA分别对粒子的内部结构和表面进行了表征. 结果表明, 3种钛酸锶钡粒子均具有钙钛矿立方相结构, 其粒径约为5~15 μm. 研究了3种形貌的钛酸锶钡粒子在含水复合弹性体介质中对电场作用的响应性能, 发现粒子形貌对其在电场中的响应能力有很大影响. 相似文献
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The crystalline phase formed during aluminum titanate at 750-1300 ℃ as well as the relationship between its content change and decomposition dynamics was mainly discussed in this paper.Dynamical equation was established for calculating the reaction activation energy.It aimed at providing dynamics basic data for taking up necessary measures to inhibit the decomposition of aluminum titanate.Experimental results showed that aluminum titanate would decompose into TiO2 and corundum at 750-1300 ℃.Content of aluminum titanate would reduce with the increase of decomposition time,and the order of decomposition rates at different temperature was 1100 > 1200 > 1000 > 900 ℃.The decomposition was a chemical reaction with control steps,and could meet the first order reaction dynamic equation-F(G) = [(1-G)-2/3-1] = Kt.According to the calculation,rate constants of different decomposition reaction dynamic equations were K900 = 2.2×10-3,K1000 = 1.2×10-2,K1100 = 4×10-1 and K1200 = 1.5×10-1,and the reaction activation energy ΔGave = 203.21 KJ/mol. 相似文献
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由钛酸盐纳米带水热制备锐钛矿型TiO2纳米带 总被引:1,自引:0,他引:1
研究了水热处理具有层状结构的钛酸钠纳米带或钛酸纳米带转化为锐钛矿型TiO2的制备过程、难易程度和相转化机理. 实验结果表明, 当水热反应温度和时间分别在160 ℃ 和24 h以内, 钛酸钠纳米带很难完全转化为锐钛矿型TiO2, 若升高反应温度并延长反应时间, 则可制得纯的锐钛矿型TiO2, 但纳米带形貌被严重破坏; 当水热反应温度和时间分别为160 ℃ 和16 h时, 1次酸洗的钛酸纳米带能够完全转化为锐钛矿型TiO2, 若钛酸纳米带经过3次强酸浸泡, 则在160 ℃下相转化时间就会缩短到12 h, 所有钛酸纳米带在转化为TiO2后的形貌仍为纳米带, 但经3次酸浸后生成的TiO2纳米带表面更光滑. 讨论了钛酸钠纳米带或钛酸纳米带转化为锐钛矿型TiO2的相转化机理. 相似文献
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以钛酸丁酯和异丙醇为原料, 采用一步法在NaOH溶液中水解后直接进行水热反应, 经焙烧处理, 得到TiO2纳米线. 采用扫描电子显微镜(SEM)、X射线衍射(XRD)和能谱分析(EDX)对产物进行了形貌、结构及成分的表征. 考察了不同水热温度、碱液浓度、水热反应时间及焙烧温度等因素对产物的影响. 结果表明, 获得较好形貌TiO2纳米线的最佳水热温度、碱液浓度和水热反应时间分别是180 ℃, 10 mol/L和24 h. 所得TiO2纳米线焙烧至950 ℃时仍为锐钛矿相, 说明本文制备方法迟滞了TiO2纳米线由锐钛矿相向金红石相的转变. 以甲基橙为目标降解物, 采用紫外-可见分光光度计研究了未掺杂和铕掺杂TiO2纳米线(Eu-TiO2)的光催化性能. 结果显示, 最佳掺铕量(摩尔分数)为1.6%. 在300 W紫外灯照射60 min时, 此掺铕量的TiO2纳米线对甲基橙溶液的降解率是未掺杂样品的1.5倍. 相似文献
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Titanate nanotubes were synthesized with hydrothermal reaction using TiO(2) and NaOH as the precursors and subsequent calcination at 400°C for 2h. The products were characterized with SEM and XRD. Adsorption and photocatalysis of methylene blue over titanate nanotubes and TiO(2) were investigated. The results indicated that titanate nanotubes exhibited a better photocatalytic degradation of methylene blue in a simultaneous adsorption and photodegradation system than that in equilibrium adsorption followed by a photodegradation system, whereas TiO(2) showed no significant differences in photocatalytic activity in the two systems. The methylene blue overall removal efficiency over TNTs in the first system even exceeded that over TiO(2). The different catalytic performances of titanate nanotubes in the two systems were tentatively attributed to different effects of adsorption of methylene blue, i.e., the promoting effect in the former and the inhibition effect in the latter. Decantation experiments showed that the titanate nanotube photocatalyst could be easily separated from the reaction medium by sedimentation. Thus titanate nanotubes with high sedimentation rates and concurrent adsorption represent a new catalyst system with a strong potential for commercial applications. 相似文献