介孔二氧化锆的水热合成和表征

以表面活性剂十二烷基磺酸钠为辅助模板剂,合成了具有较高稳定性的介孔二氧化锆。 采用TG、XRD、FT-IR以及N₂吸附-脱附等测试技术对产物进行了表征。 研究结果表明,以阴离子型表面活性剂为模板合成的二氧化锆前驱体具有层状介孔结构,经过NaOH溶液处理后再经500 ℃煅烧仍能保持其介孔结构,显示了良好的热稳定性。 在表面活性剂脱除后得到双孔分布的孔结构,其孔壁为四方晶相结构。 NaOH对其结构的形成起到了关键作用。     

MgCO3.3H2O水热分解产物及其组成

ＭｇＣＯ_３·３Ｈ_２Ｏ水热分解产物及其组成翟学良，周相廷，李美玲（河北师范大学化学系石家庄０５００１６）关键词ＭｇＣＯ_３·３Ｈ_２Ｏ，Ｍｇ_５（ＣＯ_３）_４（ＯＨ）_２·８Ｈ_２Ｏ，Ｍｇ_５（ＣＯ_３）_４（ＯＨ）_２·５Ｈ_２Ｏ，水热分解，中间体ＭｇＣＯ_...     

多羟基对苯二甲酸类化合物的合成与应用研究进展

多羟基对苯二甲酸类化合物在医药及功能材料上的应用研究得到广泛关注。 选择了其中4个具有重要应用价值的多羟基对苯二甲酸的合成及应用进行了综述。 从中归纳出以苯酚类化合物为起始原料,经Koble-Schmitt法制备,其工艺具有操作简便、生产成本低及环境友好型等特点。     

Template‐Free Hydrothermal Synthesis of Mesoporous MgO Nanostructures and Their Applications in Water Treatment

The controlled synthesis of Mg(OH)₂ nanowires and microflowers composed of nanoplates was successfully achieved by a template‐free hydrothermal synthetic method. It was found that the reaction medium played a crucial role in the morphological control of the precursor nanostructures. The high polarity of water molecules favored the polar growth of the precursor, resulting in the formation of nanowires with a diameter of 80 nm, whereas a mixed water/ethanol medium with a lower degree of polarity led to the formation of microflowers. Moreover, mesoporous MgO nanostructures could be obtained by further annealing these as‐prepared precursors in air at 500 °C for 2 h. During thermal treatment, the wire‐ and flower‐like morphologies were retained. Porosity formation was due to thermal decomposition of Mg(OH)₂ and release of H₂O. Both the mesoporous MgO nanowires and microflowers showed superior ability of adsorbing the organic dye methyl orange, and thus they are promising candidates for polluted water treatment.     

介孔分子筛V-MCM-41的水热法制备与合成机理

 以十六烷基三甲基溴化铵为模板剂,廉价的工业级高模数比(3.3)的硅酸钠为硅源,通过水热法合成了V-MCM-41介孔分子筛. 考察了合成条件对产物织构的影响,并采用低温氮吸附法分析探讨了介孔分子筛V-MCM-41的合成机理. 结果表明,模板剂用量、 pH值、加料方式、晶化温度、晶化时间、陈化时间和焙烧气氛等合成条件对介孔分子筛的制备均有影响,其中晶化温度、 pH值和模板剂用量的影响最为明显. X射线衍射谱表明合成的介孔分子筛具有六方晶体结构. 红外光谱和紫外可见光谱表明V进入了介孔分子筛的骨架结构.     

Surfactant-Free Fabrication of Copper Sulfides (CuS, Cu2S) via Hydrothermal Method

Copper sulfide nanoparticles have been synthesized from copper salicylate and thioglycolic acid by a hydrothermal method. The obtained product was analyzed by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy and photoluminescence spectroscopy. The effect of reaction time, temperature, solvent and sulfur sources was investigated.     

水热均匀沉淀法合成中孔氧化锆

以尿素为均匀沉淀剂,用水热法合成了中孔ZrO2前体,经热处理（500～550 ℃,2 h）得到晶态（t或m相）短程有序中孔ZrO2.BJH脱附孔径约为4～6 nm, BET比表面积约为60～90 m2•g－1.     

Novel Synthesis,Characterization of N1,N1,N4,N4-tetrakis (2-hydroxyethyl) terephthalamide (THETA) and Terephthalic Acid (TPA) by Depolymerization of PET Bottle Waste Using Diethanolamine

Chemical depolymerization of poly(ethylene terephthalate) (PET) waste is a possible remedy to huge amount of solid waste generation as it results in degradation products that possess a potential of recyclability. PET bottle waste was depolymerized by aminolysis using diethanolamine. Novel synthesis of N¹, N¹,N⁴,N⁴-tetrakis (2-hydroxyethyl) terephthalamide (THETA) with 73-76% yield and terephthalic acid (TPA) with 78-82% yield was achieved. The purified products were analyzed by FTIR, melting point, DSC, DTG and ¹H-NMR. THETA has various applications in the synthesis of rigid polyurethane foam, unsaturated polyester resins and also as a cross linking agent/ hardener for epoxy resins.     

BiOX (X = Cl,Br, and I) Nanoplates Prepared by Surfactant-Free Microwave Synthesis and Their Photocatalytic Performance

Russian Journal of Physical Chemistry A - Bismuth oxyhalide (BiOX; X = Cl, Br, and I) nanoplates were successfully synthesized by microwave irradiation of surfactant-free aqueous solutions. X-rays...     

植物油酸新戊二醇对苯二甲酸复合酯的合成及性能

用新戊二醇(NPG)和对苯二甲酰氯(TPA)反应生成“低聚物”中间体,当n(NPG)/n(TPA)由2.4增加至3.0时,中间体的聚合度(m)在3.5~1.45之间,收率75.5%。再将中间体与油酸、菜籽油酸进行酯化得到复合酯,收率88.5%。结果表明,复合酯的粘度随着分子量的增大而增大,粘度指数大于125,凝点低于－27℃,氧化稳定性随分子量的增大而提高,生物降解率＞70%,最大无卡咬负荷(PB)为784N,磨斑直径0.41mm,热分解温度＞250 ℃,因此植物油酸新戊二醇对苯二甲酸复合酯是性能良好的绿色润滑剂。     

Microwave Hydrothermal Synthesis and Acidity of Nanosize Gallosilicate Mesoporous Molecular Sieves

A range of nanosize alkaline‐free gallosilicate mesoporous molecular sieves (GaMMS) were synthesized using microwave hydrothermal method and various analytical and spectroscopic techniques were employed to systematically investigate the structure, coordination geometry of gallium, acidic properties and catalytic activity. These nanosize GaMMSs exhibit high surface area (240 ～ 720 m²/g), pore volume (1.06 ～ 1.49 m³/g), narrow pore size distribution and nano‐particle size between 20 and 100 nm and four‐coordinated gallium site mainly, which were characterized by XRD, N₂ adsorption/desorption, TEM, ⁷¹Ga MAS‐NMR and ICP‐AES. Mesoporosity, mesostructure and nanosize can be controlled simply by microwave irradiation time and temperature. Pyridine‐IR result reveals the coexistence of Lewis and Brönstead acid sites in these nanosize GaMMS while NH₃‐TPD profiles suggest nanosize one has stronger acid site and contains more acid sites than the conventional one. Catalytic performance was evaluated using the catalytic cumene cracking test. The result indicates that the nanosize GaMMS shows a much higher activity than that of conventional GaMCM‐41, probably due to higher concentrations of H‐form sites, external surface and fast diffusion.     

皱褶表面介孔镍钴硫化物微球的制备及其超电性能

通过一步水热法分别合成了α-NiS、Co₃S₄和CoNi₂S₄纳米介孔电极材料,并研究了其电化学性能。 X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)研究表明,介孔硫化物是由单相纳米颗粒堆叠组装而成,其中二元系的CoNi₂S₄由纳米片自组装形成了具有皱褶表面的微球形貌。 电化学性能研究表明,二元系的CoNi₂S₄比α-NiS、Co₃S₄具有更高的比电容、更佳的倍率特性和优异的循环稳定性。 在扫描速率为5 mV/s时,CoNi₂S₄材料在6 mol/L KOH电解液中比电容高达1678.3 F/g,优于α-NiS (787.4 F/g)和Co₃S₄(1532.7 F/g),在扫描速率从5 mV/s增加到100 mV/s时,其电容保持率为45.8%,比α-NiS(30.2%)和Co₃S₄(29.3%)高出约15%。 在15A/g的电流密度下,经过900次循环充-放电后,二元系的CoNi₂S₄的电容仍保持在96.3%,库伦效率保持在94.3%左右,说明镍钴双金属硫化物具有优异的循环稳定性能和充放电可逆性。     

Ligand Sensitized Flourometric Determination of Dysprosium(III) Ion Using Terephthalic Acid

Several trivalent lanthanide ions are known to exhibit excellent luminescence characteristics when they are coordinated with appropriate organic ligands. Various analytical methods have been developed to determine lanthanide ions or organic compounds by taking advantage of these luminescence characteristics. The luminescence enhancement of the lanthanide ions by complexation with organic ligands has been explained on the basis of a ligand to metal energy transfer process.     

高温水热合成具有超低介电常数的规则介孔氧化硅材料

分别以高分子三嵌段共聚物P123(PEO₂₀-PPO₇₀-PEO₂₀)和F127(PEO₁₀₆-PPO₇₀-PEO₁₀₆)为模板剂, 通过高温水热法制备了具有超低介电常数的规则介孔氧化硅材料(OMSs). 当合成温度达到200℃时, 得到的产物仍可保持规则的介孔结构. X射线衍射和氮气吸附结果表明, OMSs系列材料具有规则的二维六方或体心立方介孔结构、 大的比表面积和孔容及均一的孔径分布. ²⁹Si MAS NMR分析表明, OMSs与低温(100℃)合成产物相比具有更高的骨架缩合度, 从而具有优异的水热稳定性. 由于具有大的孔容和高的骨架缩合度, OMSs表现出了超低的介电常数. 以P123为模板剂, 200℃下合成的OMS的介电常数可达1.31. OMSs作为一类稳定的超低介电常数材料, 对于绝缘材料的发展具有潜在的应用价值.     

Synthesis of Ordered Cubic Periodic Mesoporous Silica with High Hydrothermal Stability

1 Introduction Since its first discovery in 1992[1,2], ordered mesoporous silica material with large pore size, high surface area, and high pore volume has attracted great attention for the potentially wide application     

以MCM-22为原料合成高水热稳定性的介孔材料

以合成的微孔分子筛MCM-22为原料,将其与表面活性剂及氢氧化钠一起回流溶解,再调节溶液的pH值至7～9, 使MCM-22转化为高水热稳定性的介孔材料. 所得介孔材料具有蠕虫状的均匀孔道,骨架中不含有MCM-22的微观结构单元. 该介孔材料至少含有18%的表面活性剂,经823 K焙烧脱除表面活性剂后,其孔径为2 2 nm, 比表面积为 1 038 m2/g, 孔容为0 97 cm3/g. 焙烧后的介孔材料具有非常高的水热稳定性,经沸水回流100 h后其比表面积为896 m2/g, 孔容为0 90 cm3/g, 孔径为2 1 nm, 即使经过300 h的回流,该材料仍能保持698 m2/g的比表面积和0 90 cm3/g的孔容. 固体 29Si MAS NMR结果表明,该介孔材料的高水热稳定性与其高表面缩合度有关.     

高水热稳定的有序介孔硅铝分子筛的合成与表征

将焙烧后的SBA-15先后置于微孔BEA沸石前驱体的稀释液和甘油中进行两次高温再结晶, 成功地合成了高度有序的介孔硅铝分子筛MSAMS-4, 并用XRD, TEM, FTIR, NMR和氮气吸脱附等手段对其进行表征. 水热稳定性实验结果表明, 将MSAMS-4 在100 ℃的沸水中处理120 h或在800 ℃的高温蒸气中处理6 h后, 其有序介孔结构仍然保持得相当完好.     

2,5-二酮哌嗪-N,N'-二乙酸的水热合成

亚氨基二乙酸在磷酸作用下,通过水热反应合成了2,5-二酮哌嗪-N,N'-二乙酸,收率76%,其结构经UV-Vis,1H NMR,IR,元素分析及X-射线单晶衍射表征.     

2，5-二酮哌嗪-N,N＇-二乙酸的水热合成

亚氨基二乙酸在磷酸作用下,通过水热反应合成了2,5-二酮哌嗪-N,N＇-酸,收率76％,其结构经UV-Vis,^1H NMR,IR,元素分析及X-射线单晶衍射表征。     

高温水热合成具有高稳定性的有序介孔材料

高温水热合成路线作为合成具有超高稳定性的介孔材料越来越受到人们的重视.本文对高温水热合成有序介孔材料的发展过程作一个简单的综述,合成路线包括使用碳氟表面活性剂和碳氢表面活性剂作为复合模板,有机季铵盐与碳氢表面活性剂作为复合模板以及最近报道的采用碳氢表面活性剂作为单一模板来合成系列的有序介孔材料,其组成为二氧化硅、氧化钛硅以及聚合物等.