以十六烷基三甲基溴化铵为模板剂合成MCM-41/ZSM-5复合分子筛的研究

采用阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)为模板剂、以ZSM-5为晶种,在水热晶化条件下合成了同时具有微孔和介孔的MCM-41/ZSM-5复合分子筛;并考察了陈化温度、陈化时间、晶化时间及模板剂用量等条件对合成复合分子筛的影响.通过X射线衍射、扫描电镜、高分辨率透射电镜、红外光谱及N2静态吸附法等手段对合成样...     

离子热合成磷铝分子筛

AlPO-11 molecular sieve with AEL structure was ionothermally synthesized using ionic liquid solvent as medium. The effects of ionic liquid amount, synthesis time and temperature were investigated. The structure and characteristics of molecular sieve samples were characterized by X-ray diffraction(XRD)，scanning electron microscopy (SEM), thermo gravimetric analysis(TGA). The results indicate that AlPO-11 molecular sieve could be synthesized by 1-ethyl-3-methylimidazolium bromide ([Emim]Br) ionic liquid as both the solvent and template.     

SAPO-11/Beta复合分子筛的合成及其异构化性能研究

以Beta分子筛为硅源通过水热合成法合成了SAPO-11/Beta复合分子筛,采用X射线衍射、N2物理吸脱附、扫描电镜、透视电镜-能谱分析、固体核磁及吡啶红外等方法对单分子筛、复合分子筛和机械混合分子筛的物化性质进行了表征.以正十二烷为模型化合物,在固定床反应器上考察了铂负载型分子筛催化剂的异构化性能.结果表明,复合分子筛的物理化学性质明显不同于单分子筛和机械混合分子筛,其呈现核壳结构,SAPO-11和Beta间存在化学作用,使得复合分子筛具有适宜的B酸分布.在正十二烷异构化反应中,复合分子筛催化剂的异构化性能优于单分子筛催化剂和机械混合分子筛催化剂,多支链异构体收率高.     

SAPO-31分子筛的微波加热合成、表征及催化性能

分别以异丙醇铝和磷酸为铝源和磷源,二正丁胺为模板剂,采用微波加热法成功制得AlPO4-31分子筛,并对其晶化条件进行了优化.在优化的条件下同时合成了不同含硅量的SAPO-31分子筛,采用X射线衍射、N2物理吸附、扫描电镜、固体29Si核磁共振、程序升温脱附以及吡啶吸附的红外光谱等手段对其结构和酸性进行了表征,并考察了P...     

离子热法制备多级孔AlPO_4-5分子筛

采用离子热法,以磷酸为磷源,γ-Al_2O_3为铝源,在1-丁基-3-甲基溴化咪唑离子液体中于320℃反应10 min内快速合成了多级孔AlPO_4-5分子筛,其结构和形貌经傅里叶红外光谱(FT-IR),X-射线衍射(XRD),扫描电子显微镜(SEM),氮气物理吸-脱附(BET)和透射电镜(TEM)表征。     

Cu nanoparticles immobilized on modified magnetic zeolite for the synthesis of 1,2,3‐triazoles under ultrasonic conditions

Magnetically recoverable copper nanoparticle‐loaded natural zeolite (CuNPs/MZN) as an efficient catalyst was synthesized. The Fe₃O₄ magnetic nanoparticles were immobilized into the pores of natural clinoptilolite zeolite, which were modified with epichlorohydrine and ethylenediamine species and then CuNPs were decorated on the surface of functionalized zeolite (CuNPs/MZN). The catalysts were successfully characterized by Fourier transform‐infrared, CHN, thermogravimetric analysis, inductively coupled plasma, X‐ray diffraction, scanning electron microscopy and transmission electron microscopy techniques. The 1,2,3‐triazoles were readily synthesized through using the catalyst in high yields and short reaction times under ultrasonic conditions via CuAAC reactions of aryl azides and terminal alkynes. The CuNPs/MZN was easily separated from the reaction mixture by an external magnet and reused several times successfully. The catalyst could be used for the synthesis of various organic compounds.     

Tetra-β-(2-(diethylamino)ethoxy) nickel phthalocyanine: synthesis and inclusion in MCM-41

In order to include phthalocyanine macromolecule in MCM-41 molecular sieve, a inclusion-suitable phthalocyanine derivative tetra-β-(2-(diethylamino)ethoxy) nickel phthalocyanine was synthesized, in two steps, from 4-nitrophthalonitrile and 2-(diethylamino)ethanol, and characterized by mass spectra, ¹H nuclear magnetic resonance spectroscopy, ultraviolet visible spectroscopy, infrared spectroscopy and elemental analysis, which confirmed the proposed molecular structure. The inclusion of synthesized phthalocyanine compound in MCM-41 was carried out by the in situ synthesis method using cetyltrimethyl ammonium bromide as structure template and tetraethyl orthosilicate as silica source in presence of this phthalocyanine compound. The inclusion material was studied by means of X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, nitrogen adsorption isotherm measurements, etc. Results showed that the macromolecular compound was successfully included into MCM-41, the obtained inclusion material displayed mainly prisms and globes, and the material was a kind of mesoporous materials with regularly hexagonal honeycomb array of uniform cylindrical pores and high surface area.     

应用于局域表面等离激元共振扫描显微探针的球形Au@Ag纳米粒子的合成及介电敏感性检测

局域表面等离激元共振(LSPR)显微探针的检测灵敏性主要取决于针尖上修饰的纳米粒子的LSPR性质.本文采用阴离子辅助法,在水溶液中通过调节Au核与Ag⁺的物质的量之比,实现Au核上不同厚度的Ag壳层包覆,可控地一步合成均一性好、银壳层较厚(≥10 nm)的核壳比不同的球形Au@Ag纳米粒子.通过扫描电镜(SEM)、透射电镜(TEM)及扫描透射电子显微镜X射线能谱(STM-EDS)线扫描分析对不同核壳比的Au@Ag纳米粒子进行形貌组成表征,证实了所合成核壳结构的可控性.将不同核壳比的Au@Ag纳米粒子置于不同折射率溶液中进行纳米粒子介电敏感性的研究,表明7.5 nm Au@28 nm Ag的纳米结构具有最高的品质因子.同时将不同核壳比的Au@Ag纳米粒子置于不同折射率的非导电性基底上进行单颗纳米粒子散射性质的研究,结果表明7.5 nm Au@28 nm Ag纳米粒子适合作为LSPR显微探针的高检测灵敏性纳米结构之一.     

Facile combustion synthesis of Ag2O nanoparticles using cantaloupe seeds and their multidisciplinary applications

Silver oxide nanoparticles (Ag₂O NPs) were prepared using cantaloupe (Cucumis melo) seeds as a fuel by employing a green synthesis method. The prepared Ag₂O NPs were investigated using powder X-ray diffraction (PXRD), UV–visible spectrum, Fourier transform infrared analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive spectroscopy, and photoluminescence studies. PXRD data reveal the establishment of cubic crystal structure of Ag₂O NPs. According to SEM and TEM results, the morphology of the prepared NPs was agglomerated and spherical. The photodegradation activity of the prepared Ag₂O NPs over methylene blue dye was promising under visible light irradiation. Furthermore, the antimicrobial assay of the synthesized Ag₂O NPs was carried out by the disc diffusion method against Gram-positive and Gram-negative microbial strains.     

阴离子对鼠尾草提取物中Ni盐前体绿色合成的NiO纳米粒子磁性和结构性能的影响

采用绿色合成方法,将鼠尾草提取物用作还原和封端剂合成氧化镍纳米颗粒(NiO NPs)。此外,使用各种前驱体合成了NiO NPs,并使用扫描电子显微镜对其形貌进行了分析。利用傅里叶变换红外光谱和粉末X射线衍射(PXRD)对NiO NPs的结构进行了表征,使用振动样品磁强计测量了它们的磁性。PXRD研究表明,所有合成的NiO NPs都表现出具有高结晶度的面心立方相,并且形成了具有高纯度相的NiO。磁化研究结果表明,3种镍盐(乙酸盐、氯化物和硫酸盐)前驱体合成的NiO NPs分别表现出超顺磁、软铁磁和顺磁行为。     

阴离子对鼠尾草提取物中Ni盐前体绿色合成的NiO纳米粒子磁性和结构性能的影响

采用绿色合成方法,将鼠尾草提取物用作还原和封端剂合成氧化镍纳米颗粒(NiO NPs)。此外,使用各种前驱体合成了NiO NPs,并使用扫描电子显微镜对其形貌进行了分析。利用傅里叶变换红外光谱和粉末X射线衍射(PXRD)对NiO NPs的结构进行了表征,使用振动样品磁强计测量了它们的磁性。PXRD研究表明,所有合成的NiO NPs都表现出具有高结晶度的面心立方相,并且形成了具有高纯度相的NiO。磁化研究结果表明,3种镍盐(乙酸盐、氯化物和硫酸盐)前驱体合成的NiO NPs分别表现出超顺磁、软铁磁和顺磁行为。     

双杂原子Ti-Mn-β沸石的合成、表征及催化苯酚羟化反应

采用水热合成法在SiO2-TiO2-MnO2-(TEA)2O-H2O-NH4F体系中合成了Ti-Mn-β沸石。 运用X射线衍射、红外光谱、固体紫外可见漫反射、热重-差热、扫描电子显微镜和X射线光电子能谱等技术手段对样品进行了表征,探讨了影响Ti-Mn-β沸石合成的因素。 Ti-Mn-β沸石在以H2O2为氧化剂的苯酚羟基化反应中表现出较好的催化活性,苯酚的转化率为29.8％,邻苯二酚和对苯二酚的选择性分别为70.9％和26％。     

Synthesis design and structure of a multipore zeolite with interconnected 12- and 10-MR channels

A new molecular sieve, ITQ-38, containing interconnected large and medium pores in its structure has been synthesized. The rational combination of dicationic piperidine-derivative molecules as organic structure directing agents (OSDAs) with germanium and boron atoms in alkaline media has allowed the synthesis of ITQ-38 zeolite. High-resolution transmission electron microscopy (HRTEM) has been used to elucidate the framework topology of ITQ-38, revealing the presence of domains of perfect ITQ-38 crystals as well as very small areas containing nanosized ITQ-38/ITQ-22 intergrowths. The structure of ITQ-38 is highly related to ITQ-22 and the recently described polymorph C of ITQ-39 zeolite. It shares a common building layer with ITQ-22 and contains the same building unit as the polymorph C of ITQ-39. All three structures present similar framework density, 16.1 T atoms/1000 ?(3).     

改进水热法合成SAPO-11及其酸性和异构化活性

在含异丙醇的体系中,采用程序升温水热法合成了SAPO-11分子筛,并通过X射线衍射、扫描电镜、低温氮物理吸附、氨程序升温脱附、吡啶吸附红外光谱和29Si固体核磁共振等手段进行了表征.结果表明,与常规水热合成法相比,该方法合成的SAPO-11结晶度高,晶粒小,微孔分布集中,酸性强,同时还具有较大的比表面积和微孔孔容.以该分子筛制备的Pt/SAPO-11催化剂在正十四烷临氢异构反应中表现出较高的催化活性和异构选择性.     

Y沸石的高温合成

采用甲基三乙氧基硅烷(MTS)为添加剂, 在高温(140 °C)条件下水热合成出具有六方片状形貌的Y型沸石. 相比于100 °C左右合成的Y型沸石, 高温合成的Y沸石具有更高的硅铝比值、更大的晶体宽厚比值以及对有机挥发物具有优异的吸附性能. 通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、²⁹Si固体核磁共振(NMR)、傅里叶变换红外(FTIR)光谱、碳氢氮元素分析(CHN)、水接触角等表征, 证明了所合成的新型Y沸石具有甲基基团, 它们的存在增强了疏水性能, 提高了对有机挥发物的吸附能力.     

气相转移法合成ZSM-5/SAPO-5复合分子筛

以磷酸、拟薄水铝石和硅溶胶为原料, 三乙胺为模板剂, 采用气相转移法合成了一系列ZSM-5/SAPO-5复合分子筛. 产物经X射线衍射、扫描电镜、X射线能量散射谱、红外光谱及N2 静态吸附法等手段对其进行了表征, 证明合成材料是以ZSM-5为核、SAPO-5为壳的双结构分子筛. 实验结果表明, 干胶制备条件及液相组成都影响复合分子筛的结晶. 晶化温度的提高和晶化时间的延长有利于分子筛结晶度的提高. VPT法可以减小SAPO-5和复合分子筛颗粒的直径, 改善SAPO-5在ZSM-5分子筛表面的分布. 重油裂化结果表明, 核壳结构复合分子筛对生成低碳烯烃的性能优于机械混合的样品.     

Green synthesis of silver nanoparticles using Thymus kotschyanus extract and evaluation of their antioxidant,antibacterial and cytotoxic effects

Present study used ecofriendly, cost efficient and easy method for synthesis of silver nanoparticles (Ag NPs) at the room temperature by Thymus Kotschyanus extract as reducing and capping agent. Various analytical technique including UV–Vis absorption spectroscopy determined presence of Ag NPs in the solution, the functional groups of Thymus Kotschyanus extract in the reduction and capping process of Ag NPs are approved by FT‐IR, crystallinity with the fcc plane approved from the X‐ray diffraction (XRD) pattern, energy dispersive spectroscopy (EDS) determined existence of elements in the sample, surface morphology, diverse shapes and size of present Ag NPs were showed by using scanning electron microscopy (SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM). Beginning and end destroy temperature of present silver nanoparticles were determined by thermal gravimetric spectroscopy (TGA). In addition, antibacterial, antioxidant and cytotoxicity properties of Ag NPs were studied. Agar disk and agar well diffusion are the methods to determined antibacterial properties of synthesized Ag NPs. Also MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) were recognized by macro broth dilution assay. DPPH free radical scavenging assay was used for antioxidant property and compare to butylated hydroxytoluene (BHT) as standard antioxidant that showed high antioxidant activity more than BHT. Synthesized Ag NPs have great cell viability in a dose depended manner and demonstrate that this method for synthesis silver nanoparticles provided nontoxic. The average diameter of synthesized Ag NPs was about 50–60 nm.     

Polyelectrolyte-surfactant complex as a template for the synthesis of zeolites with intracrystalline mesopores

Mesoporous zeolite silicalite-1 and Al-ZSM-5 with intracrystalline mesopores were synthesized with polyelectrolyte-surfactant complex as the template. Complex colloids were first formed by self-assembly of the anionic polymer poly(acrylic acid) (PAA) and the cationic surfactant cetyltrimethylammonium bromide (CTAB) in basic solution. During the synthesis procedure, upon the addition of the silica source, microporous template (tetrapropylammonium hydroxide), and NaCl, these PAA/CTA complex colloids underwent dissociation and gave rise to the formation of hollow silica spheres with mesoporous shells templated by CTAB micelles and PAA domains as the core. Under hydrothermal treatment, the hollow silica spheres gradually merged together to form larger particles with the PAA domains embedded as the space occupant, which acted as a template for intracrystalline mesopores during the crystallization of the zeolite framework. Amphiphilic organosilane was used to enhance the connection between the PAA domain and the silica phase during the synthesis. After calcination, single crystal-like zeolite particles with intracrystalline mesopores of about 5-20 nm were obtained, as characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N(2) adsorption measurements. With the addition of an aluminum source in the synthesis, mesoporous zeolite Al-ZSM-5 with intracrystalline mesopores was also synthesized, and enhanced catalytic property was observed with mesoporous Al-ZSM-5 in acetalization of cyclohexanone with methanol.     

离子热法合成多级孔CuAPO-5分子筛

采用丁二酸、氯化胆碱与四乙基溴化铵三元低共熔体为溶剂和模板剂,借助微波辐射快速合成了具有多级孔结构的CuAPO-5分子筛.系统地考察了P₂O₅/Al₂O₃、HF/Al₂O₃与CuO/Al₂O₃的物质量之比,铝源及铜源对CuAPO-5分子筛合成的影响.利用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)和N₂物理吸脱附等检测手段对合成产物的结晶度、形貌和孔结构等进行了表征.通过SEM可知在一定的条件下,可得到具有六角纳米盘状特殊形貌的CuAPO-5分子筛.N₂物理吸脱附、SEM和TEM分析表明该分子筛是一种同时存在微孔和介孔的多级孔磷酸铝分子筛材料.     

离子热法合成多级孔CuAPO-5分子筛

采用丁二酸、氯化胆碱与四乙基溴化铵三元低共熔体为溶剂和模板剂,借助微波辐射快速合成了具有多级孔结构的CuAPO-5分子筛。系统地考察了P2O5/Al2O3、HF/Al2O3与Cu O/Al2O3的物质量之比,铝源及铜源对CuAPO-5分子筛合成的影响。利用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)和N2物理吸脱附等检测手段对合成产物的结晶度、形貌和孔结构等进行了表征。通过SEM可知在一定的条件下,可得到具有六角纳米盘状特殊形貌的CuAPO-5分子筛。N2物理吸脱附、SEM和TEM分析表明该分子筛是一种同时存在微孔和介孔的多级孔磷酸铝分子筛材料。