CTAB作用下纳米复合材料Ag/ZnO-SnO2的制备与光催化降解罗丹明B

在模板剂溴化十六烷基三甲基胺(CTAB)作用下,采用溶胶-凝胶法再结合程序升温溶剂热法制备了纳米复合材料Ag/ZnO-SnO2(CTAB),其中Ag,Zn,Sn摩尔比为0.1∶2∶1.利用X射线衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)、扫描电子显微镜配合X射线能量色散谱(SEM-EDS)和N2吸附-脱附测定等方法对复合材料的组成、结构及形貌等进行了表征.结果表明,该复合材料具有纤锌矿和金红石结构,Ag以单质形式存在.与未经CTAB作用的样品相比,Ag/ZnO-SnO2(CTAB)颗粒分布更均匀,且呈现规则的纳米棒状结构.复合材料在紫外光和可见光作用下对罗丹明B(RhB)的光催化降解结果显示,样品Ag/ZnO-SnO2(CTAB)的光催化活性明显高于Ag/ZnO-SnO2、ZnO-SnO2、ZnO和商用P-25.     

不同阴/阳离子表面活性剂复配体系的缔合结构研究

测定了十二烷基磺酸钠(AS)/十六烷基三甲基溴化铵(CTAB)/正丁醇(n-C4H9OH)/正庚烷(n-C7H16)/水(H2O),十二烷基硫酸钠(SDS)/十六烷基三甲基溴化铵(CTAB)/正丁醇(n-C4H9OH)/正庚烷(n-C7H16)/水(H2O)体系的微乳液正四面体相图,并用电导法划分了AS/CTAB/n-C4H9OH/n-C7H16/H2O体系微乳液的结构(W/O,B.C.和O/W);同时研究AS/CTAB/n-C4H9OH/n-C7H16/H2O/盐类(NaCl,CaCl2或AlCl3)体系和SDS/CTAB/n-C4H9OH/n-C7H16/H2O/盐类(NaCl,CaCl2或AlCl3)体系形成中相微乳的盐宽,从中得出上述两体系中相微乳的盐宽随盐类阳离子价态的增大而的规律。     

微乳液法低温制备纳米金红石型二氧化钛的研究

以TiCl₄为原料、在十六烷基三甲基溴化铵/正己醇/水组成的微乳液体系中、在较低温度下,制备了球形、花状、捆绑丝和星形的金红石型二氧化钛纳米颗粒。研究了w值(水与CTAB物质的量之比)、反应物浓度、反应温度以及P值(正己醇与CTAB的物质的量之比)等因素对产品形貌的影响,并用TEM、XRD对产品进行了表征。     

水热合成Co_3O_4的制备参数调变及其催化分解N_2O性能（英文）

以十六烷基三甲基溴化胺(CTAB)为模板剂,通过调变CTAB浓度水热合成了氧化钴前驱体,焙烧制得棒状形貌的Co_3O_4,在其表面浸渍K_2CO_3溶液制得K改性的Co_3O_4催化剂,用于N_2O分解。用X射线衍射(XRD)、N_2物理吸附(BET)、扫描电镜(SEM)、X射线光电子能谱(XPS)、H_2程序升温还原(H_2-TPR)和O_2程序升温脱附(O_2-TPD)等技术对催化剂进行了表征,考察了CTAB/钴及尿素/钴物质的量比等制备参数对Co_3O_4催化分解N_2O活性的影响。结果表明,CTAB浓度为0.05 mol/L、CTAB/钴离子物质的量比为1、尿素/钴离子物质的量比为4时,所制备的Co_3O_4催化剂具有较高的N_2O分解活性,而K改性可以进一步提升其催化性能。K改性的Co_3O_4在有氧有水气氛中400℃下进行N_2O分解反应,50 h后N_2O转化率仍保持在91%以上。     

明胶和阳离子表面活性剂CTAB的相互作用

采用电导法、荧光法、pH等方法研究了明胶与十六烷基三甲基溴化铵 (CTAB)的相互作用.结果表明,在CTAB/明胶 /水体系中,明胶浓度的增大使得CTAB分子的cac₁,cac₂,cmc值均上升,胶束的聚集数下降.冷冻蚀刻透射电镜实验(FFTEM)的结果证实了明胶分子与CTAB分子之间形成了复合物,随着CTAB浓度的增加,结构从线状、卷曲、珍珠项链状、棒状至网状依次变化.     

合成条件对径向有序介孔二氧化硅中空亚微米球的形貌和结构的影响

本文以硬模板与软模板结合的双模板方法(十六烷基三甲基溴化铵(CTAB)为介孔模板,聚苯乙烯(PS)球为中空模板),通过自组装制备出有良好分离性和单分散性且具有径向介孔的二氧化硅中空亚微米球.研究表明CTAB、TEOS的用量,催化剂的种类对二氧化硅中空亚微米球的形貌、壁厚、产品纯度等都有很大的影响.在保持其它实验条件不变的情况下,通过分别单独调节CTAB和TEOS的用量或同时调节CTAB和TEOS的用量,得出最佳原料配比是:TEOS/CTAB/NH3/乙醇/水的摩尔比是1:0.27:9.8:304:2955,TEOS/聚苯乙烯球的质量比是4/1.催化剂的种类对中空亚微米球的形貌也有较大影响,当NaOH(浓度为1 mol/L)的用量为0.05—0.10 mL时,生成由小粒子聚集而成的亚微米球;随着NaOH用量增大到0.10—0.20 mL,小粒子逐渐粘合在一起,亚微米球表面逐渐变光滑;进一步增大NaOH用量为0.20—0.30 mL则导致杂质小粒子的出现.在实验结果和文献报道的基础上,讨论并提出了径向有序介孔二氧化硅中空亚微米球的形成机理.     

钛铁矿型CoTiO3纳米材料的制备及性能表征

以Co(NO₃)₂•6H₂O和TiO₂ (P-25)为原料, 在十六烷基三甲基溴化铵(CTAB)/水形成的胶束溶液中, 首先制得纳米氧化钴Co₃O₄-TiO₂复合材料, 该复合材料经600和700 ℃煅烧后制备了钛铁矿型CoTiO₃纳米材料. 以X射线衍射(XRD)、透射电子显微镜(TEM)、紫外-可见(UV-vis)、拉曼(Raman)光谱和X射线光电子能谱(XPS)对其结构特征和光谱性能进行了研究. 用TEM形貌观察, 粒子基本为球形; 纳米CoTiO₃的UV-vis吸收峰明显红移; 经Raman光谱和XPS分析, 进一步表明600和700 ℃煅烧后形成了Ti—O—Co键.     

无探针紫外光谱法测定CTAB的第二临界胶束浓度

应用无探针的紫外吸收分光光谱法(UV)测定了十六烷基三甲基溴化铵(CTAB)溶液的第一、第二临界胶束浓度(CMC), 并用¹H NMR谱和动态光散射的实验方法检测到了两个浓度时溶液中聚集体的转变, 从而验证了无探针紫外光谱法测定CTAB溶液第二临界胶束浓度的可行性. 此外, 我们还利用紫外光谱法研究了CTAB/KBr体系, 证实KBr可诱导CTAB形成蠕虫状胶束.     

CTAB作用下纳米复合材料ZnO-TiO2制备与多模式光催化降解罗丹明B

在模板剂十六烷基三甲基溴化铵作用下,通过溶胶-凝胶与程序升温溶剂热法制备了纳米复合材料ZnOTiO2(CTAB).经X-射线衍射(XRD)、紫外-可见漫反射吸收光谱(UV-Vis/DRS)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和N2吸附-脱附测试等手段对其组成、结构和形貌等进行了表征.结果显示,合成产物ZnO-TiO2(CTAB)主要晶型为ZnO纤锌矿,并部分生成ZnTiO3.同时,该合成产物经CTAB作用后,其对光的吸收发生明显红移,且平均孔径明显变小,BET值增大.在紫外光、可见光、模拟日光和微波辅助等不同模式光催化降解罗丹明B的实验研究中,与未经CTAB作用的样品ZnO-TiO2相比,ZnO-TiO2(CTAB)具有更高的光催化性能.同时,该复合材料在紫外光条件下,对甲基橙、罗丹明B、结晶紫、亚甲基蓝和龙胆紫5种不同结构染料的光催化中均表现出良好的降解效果.     

辐射状钯纳米花的可控合成及其电催化性能的研究

水体系中,以十六烷基三甲基溴化铵(CTAB)和L-精氨酸为表面活性剂,抗坏血酸还原PdCl42-,制得了直径范围在50~80 nm之间的辐射状钯纳米花.实验表明,CTAB和L-精氨酸对辐射状钯纳米花的形成起着协同作用.此外,还研究了辐射状钯纳米花对甲酸氧化的电催化活性.在0.5 mol/L H2SO4+0.5 mol/L HCOOH溶液中的循环伏安结果表明,辐射状钯纳米花修饰电极在酸性溶液中电催化氧化甲酸的峰电流密度约为101 mA/mg,明显优于实心钯纳米粒子修饰的电极(峰电流密度为50 mA/mg),且表现出较高的稳定性.     

Synthesis and Characterization of Cu2S Nanostructures Via Hydrothermal Method by a Polymeric Precursor

Cu₂S nanostructures were synthesized successfully via hydrothermal approach with new precursor. The precursor was characterized via thermal gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The products were characterized with X-ray diffraction, scanning electron microscopy, transition electron microscopy, energy-dispersive X-ray spectroscopy, FT-IR, room temperature photoluminescence spectroscopy and ultraviolet–visible spectroscopy. The effect of different parameters such as Cu²⁺/TGA mole ratio, reaction time and temperature were investigated on product size and morphology.     

Synthesis and characterization of core-shell selenium/carbon colloids and hollow carbon capsules

A novel Se/C nanocomposite with core-shell structures has been prepared through a facile one-pot microwave-induced hydrothermal process. The new material consists of a trigonal-Se (t-Se) core and an amorphous-C (a-C) shell. The Se/C composite can be converted to hollow carbon capsules by thermal treatment. These products were characterized by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED), energy-dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS).     

第二近红外窗口荧光Ag2Te量子点的合成

以巯基辛烷为表面配体, 通过调控Ag前体和Te前体的比例, 制备了第二近红外窗口荧光Ag₂Te量子点. 采用透射电子显微镜(TEM)、 X射线衍射光谱(XRD)、 X射线光电子能谱(XPS)、 紫外-可见-近红外吸收光谱和荧光光谱等对产物进行了表征. 结果表明, 制得了粒径均一、 分散性好的油溶性Ag₂Te量子点, 其最大荧光发射波长位于1320 nm, 荧光量子产率高达4.2%.     

Peptide recognition via hierarchical imprinting

Silica particles containing immobilised peptidic templates have been used for the generation of hierarchically imprinted polymers. The pores of the silica mould were filled with a mixture of monomers/initiator and polymerised, followed by dissolution of the silica template. This method leaves behind imprinted polymers with binding sites located at the surface, which are capable of recognising larger molecules with the same immobilised epitope. All the products resulting from solid-phase synthesis of peptides were characterised by elemental analysis, FT-IR spectroscopy and fluorescence microscopy. The hierarchically imprinted polymers generated from these products were characterised by elemental analysis, FT-IR spectroscopy, fluorescence microscopy, scanning electron microscopy (SEM) and nitrogen adsorption, providing evidence concerning the reproducibility of each step. The chromatographic properties of the materials have been investigated and the advantages of the immobilisation method have been proven. The materials exhibit selectivity for their templates and other structurally related dipeptides. Furthermore, the polymers proved to be capable of recognising larger peptides containing the immobilised sequence.     

两相热法处理Cyanex 301-Ag+/Cu2+萃取体系制备Ag2S纳米和CuS微米材料

以Cyanex 301萃取剂为硫源,分别萃取Ag+和Cu2+,两相热法制备了Ag2S纳米颗粒和CuS微结构,采用X射线粉末衍射、紫外可见光谱、红外光谱以及电子显微镜对产物进行了表征。 表明制得的Ag2S和CuS分别为单斜相和六方相。 产物粒径随着反应温度的升高而增大,因而可通过加热温度调控产物尺寸,另外还考虑了其它反应条件对产物的影响。     

Microwave-assisted in situ synthesis of fluorescent gold nanoclusters with BSA/montmorillonite and application on latent fingermark imaging

A method for in situ preparation of fluorescent gold nanoclusters(Au NCs) with bovine serum albumin/montmorillonite composite powder(Au NC-BSA/MMT) was developed, and the products were used to detect latent fingermarks. In this work, Au NCs were "grown" both inside and on the surface of BSA/MMT clay using one-step reduction of HAu Cl4 by BSA. The as-prepared Au NC-BSA/MMT nanocomposites emit intensive red fluorescence under the excitation of UV-visible light and show stable chemical features and low toxicity. The obtained fluorescent powders were characterized by UV-visible absorption spectroscopy,fluorescence spectroscopy, infrared spectroscopy, transmission electron microscopy/high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction to depict their sizes, structural information and optical features. Given their environmentally friendly preparation, simple operation, low cost, efficient UVvisible radiation-dependent photoluminescence and good affinity with finger residues, the in situ synthesized Au NC-BSA/MMT nanocomposite powders were used as an alternative fluorescent developing reagent for developing latent fingermarks deposited on various object surfaces(such as glass, aluminum foil, painted metal, plastic products and weighing papers) for individual identification. As results, the developed fingermarks with clear patterns and satisfactory level-2(minutiae points) and level-3(sweat pores) ridge details were obtained. Notably, treated prints could be excited by red light and emitted near infrared fluorescence, which was beneficial to avoid background interference and reduce the damage caused by UV light. With the advantages of the simple preparation process and good enhancement performance for latent fingermarks, the proposed method might be used in the preparation of various fluorescent probes for detecting trace evidence in forensic sciences.     

Microwave-assisted <Emphasis Type="Italic">in situ</Emphasis> synthesis of fluorescent gold nanoclusters with BSA/montmorillonite and application on latent fingermark imaging

A method for in situ preparation of fluorescent gold nanoclusters (AuNCs) with bovine serum albumin/montmorillonite composite powder (AuNC-BSA/MMT) was developed, and the products were used to detect latent fingermarks. In this work, AuNCs were “grown” both inside and on the surface of BSA/MMT clay using one-step reduction of HAuCl4 by BSA. The as-prepared AuNC-BSA/MMT nanocomposites emit intensive red fluorescence under the excitation of UV-visible light and show stable chemical features and low toxicity. The obtained fluorescent powders were characterized by UV-visible absorption spectroscopy, fluorescence spectroscopy, infrared spectroscopy, transmission electron microscopy/high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction to depict their sizes, structural information and optical features. Given their environmentally friendly preparation, simple operation, low cost, efficient UVvisible radiation-dependent photoluminescence and good affinity with finger residues, the in situ synthesized AuNC-BSA/MMT nanocomposite powders were used as an alternative fluorescent developing reagent for developing latent fingermarks deposited on various object surfaces (such as glass, aluminum foil, painted metal, plastic products and weighing papers) for individual identification. As results, the developed fingermarks with clear patterns and satisfactory level-2 (minutiae points) and level-3 (sweat pores) ridge details were obtained. Notably, treated prints could be excited by red light and emitted near infrared fluorescence, which was beneficial to avoid background interference and reduce the damage caused by UV light. With the advantages of the simple preparation process and good enhancement performance for latent fingermarks, the proposed method might be used in the preparation of various fluorescent probes for detecting trace evidence in forensic sciences.     

Fabrication of Hexagonal Boron Nitride Nanosheets by Using a Simple Thermal Exfoliation Process

A simple and inexpensive method to exfoliate boron nitride powder to form boron nitride nanosheets (BNNSs) with few layers was achieved by using a physically thermal process. The obtained BNNSs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), IR spectroscopy, and Raman spectroscopy. The size distribution of the sheets and average sheet size is in the range of 80–380 nm and 200±62 nm, respectively, and the pure phase h‐BN products were confirmed. XPS result showed the B/N atomic ratio to be 0.99. In addition, the BNNSs can well disperse in aqueous solution to form a cloudy suspension and importantly, can remain suspended for 1 month without precipitate, which would have good potential in a wide range of applications.     

Synthesis and Characterization of Core‐Shell Selenium/Carbon Colloids and Hollow Carbon Capsules

A novel Se/C nanocomposite with core‐shell structures has been prepared through a facile one‐pot microwave‐induced hydrothermal process. The new material consists of a trigonal‐Se (t‐Se) core and an amorphous‐C (a‐C) shell. The Se/C composite can be converted to hollow carbon capsules by thermal treatment. These products were characterized by transmission electron microscopy (TEM), powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED), energy‐dispersive X‐ray (EDX) spectroscopy, and X‐ray photoelectron spectroscopy (XPS).     

Zn3(OH)2V2O7·2H2O纳米片的水热制备

采用硝酸锌、五氧化二钒和氢氧化钠作为反应物,通过一个简单的CTAB辅助的水热方法制备了Zn₃(OH)₂V₂O₇·2H₂O纳米片。运用XRD,ICP-AES,FTIR,HRTEM,EDS,FE-SEM对产物的晶相和形貌进行了表征。结果表明CTAB在控制产物的形貌、尺寸分布和自组装过程中起着关键作用。同时我们研究了产物的晶体生长行为和自组装过程。