三元添加剂水溶液体系制备CaCO3空心球

利用原位聚合方法, 通过加入一定量的引发剂使甲基丙烯酸原位聚合, 在三嵌段共聚物(P123)、聚甲基丙烯酸(PMAA)和十二烷基硫酸钠(SDS)的三元添加剂混合溶液体系中成功地制备了CaCO3空心球. 采用扫描电子显微镜(SEM)和X射线粉末衍射(XRD)对合成样品的形貌、结构进行了表征. 结果显示, 方解石CaCO3空心球直径约0.5-2 μm. 空心球壁由直径约25-35 nm的圆形粒子组成, 壁厚约100-300 nm. 利用核鄄壳机理解释了空心球结构的形成过程.     

碳纳米管负载氧化铝材料的制备及其吸附水中氟离子的研究

采用碳纳米管和硝酸铝制备了碳纳米管负载氧化铝新型除氟材料.X射线衍射检测发现,当焙烧温度低于850℃时,氧化铝为无定形态,当焙烧温度为1050℃时,氧化铝为α形态,扫描电子显微镜观察到碳纳米管与氧化铝均匀掺杂.同时用碳纳米管负载氧化铝复合材料进行水中氟离子的吸附研究,结果表明,该复合材料具有优良的除氟效能.氧化铝负载量为30%、焙烧温度为450℃条件下制备的碳纳米管负载氧化铝复合材料的吸附除氟能力是γ-氧化铝的2.0～3.5倍,与IRA-410聚合树脂的吸附除氟能力相当,适宜pH范围为5.0～9.0,吸附等温线符合Freundlich方程.     

以离子液体为铝源和模板合成氧化铝纳米纤维

以咪唑类氯铝酸盐离子液体(x Al Cl_3-[C_(10)mim]Cl)为模板和铝源,采用溶胶-凝胶法合成了氧化铝纳米纤维.考察了氯铝酸盐离子液体中Al Cl_3的摩尔分数以及焙烧温度对纤维状氧化铝合成的影响,通过X射线衍射仪(XRD)、场发射透射电子显微镜(TEM)和物理吸附仪对样品进行了表征.研究结果表明,氯铝酸盐离子液体可以同时作为模板剂和铝源合成具有一定形貌的氧化铝.当Al Cl_3的摩尔分数x(Al Cl_3)=0.5时,可以合成出纳米纤维状氧化铝,纳米纤维直径约为2 nm,长度约为200 nm,比表面积为238.38 m~2/g,孔容为0.54 cm~3/g,平均孔径为8.43 nm.合成的氧化铝具有高的热稳定性,在900℃下焙烧依然能够很好地保持其形貌结构和γ晶型.此外,提出了氢键共π-π键堆积机理来解释超细纤维氧化铝的合成过程.     

三元添加剂水溶液体系合成亚微米硫化锌空心球

利用仿生合成方法,通过加入一定量的引发剂使甲基丙烯酸原位聚合,在聚乙二醇(PEG)、聚甲基丙烯酸(PMAA)和十二烷基硫酸钠(SDS)的三元添加剂混合溶液体系中控制了合成硫化锌晶体,提出了一种简单易行的合成硫化锌空心球的新方法.采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线粉末衍射(XRD)及紫外吸收光谱等手段对合成样品的形貌、结构及性能进行了表征.TEM结果显示,ZnS空心球的直径约为300～400nm,其壳层的厚度约为50nm.SEM结果显示,空心球的外壳是由初级纳米粒子定向熔合排列形成的蠕虫状结构紧密组装而成.由于相应的胶束结构的改变,表面活性剂SDS浓度的变化明显改变了ZnS产物的形貌,在较高浓度的SDS溶液中得到了ZnS片状晶体的球形聚集体.利用核-壳机理初步解释了空心球结构的形成过程.     

模板法制备的掺镧氧化镍多孔空心微球及电化学电容性能

采用模板法在水热条件下合成了掺La的NiO多孔空心球。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电镜(SEM)、透射电子显微镜(TEM)和X射线能谱(EDS)对其结构和形貌进行了表征。采用循环伏安、恒流充放电技术对其电化学性能进行了测试,研究结果表明,La掺杂对NiO空心球的粒径、壳层厚度和电化学性能均有显著影响,当La掺杂量为1.30mol%时,掺杂后NiO的单电极比电容达到205 F.g-1,比未掺杂的提高了50%,并且表现出良好的循环稳定性和可逆性。     

高分散纳米薄水铝石和纳米氧化铝的制备及其对甲基橙的吸附性能

以硝酸铝为铝源,尿素为沉淀剂,采用无模板水热法合成纳米薄水铝石(γ-AlO(OH))。在不同温度下煅烧后,得到氧化铝产物(γ-Al2O_3和θ-Al2O_3)。利用X射线衍射(XRD)、场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FTIR)、氮气吸附-脱附法和紫外-可见分光光度计(UV-Vis)对产物进行了表征分析。并且研究了产物对甲基橙(MO)的吸附性能,系统地考察了吸附时间、溶液的pH值、甲基橙浓度及循环使用对产物吸附性能的影响。此外,还对吸附过程进行了相关吸附理论研究。结果表明:与其他方法所制备的产物相比,通过该方法获得的产物的分散性更高,形态更均匀和完整。产物为高度分散的纳米捆扎状结构。γ-AlO(OH)对甲基橙的最大吸附量达1 492.5 mg·g~(-1)。另外,产物的吸附机制包含化学作用吸附机制和静电作用吸附机制等。3种产物对甲基橙的吸附均符合Langmuir单分子层吸附模型,吸附过程均符合二级动力学特征。     

水相一步合成锐钛矿型二氧化钛空心球

报道了水相一步直接合成晶体TiO2空心球的方法. 以水溶性的过氧化钛配合物(peroxo-titanium complex, PTC)为前驱体、聚苯乙烯(polystyrene, PS)球为模板, 在水溶液体系中可直接制备得到锐钛矿型纳米TiO2空心球. 与传统的模板法相比, 模板的包覆、去除及TiO2壳层的晶化等步骤在水相中可一步完成. 利用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)及热重分析仪(TGA)对所合成的纳米TiO2空心球进行了表征, 同时推断了可能的反应机理.     

一步溶剂热法合成C掺杂介孔TiO_2可见光光催化材料

在无模板剂的条件下,以钛酸四丁酯为钛源,采用一步溶剂热法,在乙醇体系中合成出C掺杂TiO2球状介孔可见光光催化材料.通过X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、氮气吸附-脱附仪、X射线光电子能谱(XPS)、固体漫反射(UV-Vis)以及光降解罗丹明B实验等对其进行了结构表征和性能测试.实验结果表明,合成样品为锐钛矿晶型,材料表现为由纳米粒子堆积而成的大小均一的球形形貌.TiO2材料的结晶度和粒子形貌大小可以通过乙酸加入量来进行调控,这对于实际应用具有重要意义.同时,通过测试证明样品中的C原子进入TiO2晶格内部,取代了O原子的位置,窄化了TiO2内部的能带结构,从而大大提高了材料的可见光光催化活性,结果证明合成材料对污染物具有很好的吸附性能和光降解性能.     

完美骨架全硅β沸石性质研究Ⅰ.合成全硅β沸石与脱铝β沸石的性质比较

以四乙基氢氧化铵为模板剂,正硅酸乙酯为硅源,静置水热法合成全硅β沸石.用硝酸(13 mol/L)对硅铝比(Si/Al)为20的Na-β沸石回流脱铝.焙烧后的上述两样品经粉末X射线衍射、低温氮吸附、核磁共振、红外光谱、吸附等温线等表征,发现合成的全硅β沸石骨架与孔道结构完美并具有很高的表面疏水/亲有机物的吸附特性.     

α-Al2O3纳米片的自燃烧法控制合成及其抛光性能

以硝酸铝和甘氨酸为原料,采用自燃烧法,在不改变制备工艺的前提下,通过调整原料的配比,成功实现了α-Al2O3由纳米粒子到纳米片的可控合成,获得了分散性良好、尺寸均一的α-Al2O3纳米片.并通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱、热重.差示热分析法(TG-DTA)等手段对产物形貌、结构及前驱物的热性质等进行了研究.系统探讨了α-Al2O3纳米材料不同形貌和尺寸对其抛光性能的影响,结果表明,尺寸小且为片状纳米结构的α-Al2O3具有最佳抛光性能.这些实验结果对于α-Al2O3纳米材料的工业生产及其在抛光领域的实际应用具有借鉴意义.     

一种新型的空心镍纳米球的合成

通过以二氧化硅粒子作为模板和金纳米粒子为表面晶种的方法制备了壳厚度可控的镍空心球。采用TEM﹑XRD对二氧化硅/镍复合球和镍空心球进行了表征和研究。结果表明镍纳米壳是由似针状的面心立方的镍纳米粒子构成的，碱溶液处理过程不影响镍纳米壳的形貌。高温处理显示镍空心球具有良好的热稳定性。     

Fabrication of polystyrene–PbS core-shell and hollow PbS microspheres with sulfonated polystyrene templates

Uniform inorganic- (PbS) coated polymer core-shell and hollow PbS microspheres were prepared by an easy and economical approach. Monodisperse polystyrene (PS) microspheres were used as templates, as well as the core of the composite spheres; lead sulfide shells were obtained through the reaction of lead acetate (Pb(CH₃COO)₂) and thioacetamide (TAA) at room temperature. The morphologies and structures of the as-synthesized products were systematically characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), and Fourier transform infrared spectra (FTIR). The fluorescence property of the as-synthesized product was also investigated. A reasonable mechanism for the formation of PS–PbS core-shell and hollow PbS microspheres was discussed. According to a series of parallel experiments, effects of related experimental parameters were also carefully investigated, such as the molar ratio of Pb(CH₃COO)₂ to TAA, reaction temperature, etc.     

Fabrication of hollow titania microspheres with tailored shell thickness

Submicron hollow spheres are an interesting class of materials that receive significant attention nowadays. Closed and mechanically robust homogeneous hollow titania microspheres with as much shell thickness as 130 nm were fabricated by coating polystyrene beads with titania nanoparticles using sol–gel chemistry and subsequently removing the core either via heating or a chemical dissolution process. The thickness of the titania shell deposited on polystyrene core was finely tuned between 100 and 130 nm by varying the concentration of titania precursor, i.e., Ti(OEt)₄ salt from 0.5 to 2 mM during the coating process. The obtained hybrid core–shell particles and hollow microspheres were characterized by scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction, and thermo-gravimetric analysis. The approach employed is well suited to the preparation of titania-coated polystyrene hybrid particles and hollow titania spheres, which can find their applications as novel building blocks with unique optical properties for fabrication of advanced materials, catalyst, and drug delivery system.     

Jingle-bell-shaped ferrite hollow sphere with a noble metal core: Simple synthesis and their magnetic and antibacterial properties

In this paper, a simple strategy is developed for rational fabrication of a class of jingle-bell-shaped hollow structured nanomaterials marked as Ag@MFe₂O₄ (M=Ni, Co, Mg, Zn), consisting of ferrite hollow shells and metal nanoparticle cores, using highly uniform colloidal Ag@C microspheres as template. The final composites were obtained by direct adsorption of metal cations Fe³⁺ and M²⁺ on the surface of the Ag@C spheres followed by calcination process to remove the middle carbon shell and transform the metal ions into pure phase ferrites. The as-prepared composites were characterized by X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray analysis (EDX), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis spectroscopy and SQUID magnetometer. The results showed that the composites possess the magnetic property of the ferrite shell and the optical together with antibacterial property of the Ag core.     

苯胺与吡咯共聚物空心球的自组装制备及性能

以碱性溶液为反应介质,苯胺和吡咯为单体,采用稀释聚合法制备苯胺-吡咯共聚物自组装空心微球.研究了搅拌条件、共聚单体摩尔比、聚合反应介质和聚合时间对共聚物形貌的影响.采用扫描电子显微镜、透射电子显微镜、红外光谱、广角X射线衍射、热重分析仪和四探针技术表征了共聚物的形貌、结构和性能.研究结果表明,聚合反应条件对共聚物的形貌有重大影响,通过调整聚合反应条件,可以实现共聚物形貌的有效调控.共聚单体总摩尔浓度为0.05 mol/L,氨水溶液作为反应介质,在静态条件下反应24 h可以得到尺寸均一、平均外直径为610～863 nm,壳厚144～162 nm的自组装共聚物空心微球.同时,研究了共聚物对银离子的吸附性能,结果表明共聚物对银离子有还原作用,吸附后共聚物表面有纳米银的生成.     

自催化还原制备微米和纳米级空心镍球的研究

提出了一种新型的制备超细空心金属镍粉的方法.通过FESEM,TEM和XRD衍射对该制备方法进行了研究,并考察了有关工艺参数对产物粒径和粒度分布的影响.研究认为,通过在胶核表面发生自催化还原反应,形成金属镍壳,同时胶核发生自分解,最后可得到空心金属镍球.控制反应物浓度和NaOH的配比可得到粒径均匀的镍球;通过调整这两个参数可得到粒度在微米或纳米尺度的空心镍球.     

Preparation of CaCO_3 Hollow Spheres in an Aqueous Binary-additive System

CaCO3 hollow spheres were prepared easily in anion surfactants （sodium dodecylbenzenesulfonate （SDBS）） and aspartic （Asp） acid binary-additive system by using an easy rapid agitation method. The as-prepared products were characterized with scanning electron microscopy （SEM）, FT-IR and X-ray diffraction. The results suggested that the CaCO3 hollow spheres have diameters ranging from 1 to 2 μm, and their wall is constituted of many nano-particles. Moreover, the possible formation mechanism of the hollow spherical structure was proposed.     

壳壁上具有介孔的Si/Al复合氧化物中空微球的制备

近年来,由于中空的球形材料具有良好的表面渗透性、低密度和高比表面积等性质而受到人们的普遍关注,在无机中空球的制备过程中,所采用的方法大多为模板法,合成的无机中空球主要以SiO2、金属氧化物(如TiO2和SnO2等)及金属(金、银、钯和镍等)为主,而有关二元复合氧化物中空球合成的研究报道较少,制备球壳上具有介孔的中空球已有报道,但是,其得到的介孔常常不均一,因此,将中空球形材料、复合氧化物和均一介孔有效地结合起来将是非常有意义一项工作。     

Chelating ligand-mediated synthesis of hollow ZnS microspheres and its optical properties

Monodispersed hollow ZnS microspheres have been successfully synthesized by a facile ethylenediamine tetraacetic acid (EDTA) mediated hydrothermal route. The sizes of the hollow spheres vary from 1.5 to 3.5 microm when the reaction temperature varied from 130 to 230 degrees C. The formation of these hollow spheres is attributed to the oriented aggregation of ZnS nanocrystals around the gas-liquid interface between H(2)S and water. EDTA plays important role as chelating ligand and capping reagent, which regulates the release of Zn(2+) ions for the formation of ZnS hollow spheres. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis spectroscopy, photoluminescence, and Raman spectroscopy. The obtained ZnS hollow spheres show a sharp and photostable UV emission approximately 370 nm, which is attributed to the recombination process associated with interstitial sulfur vacancy.     

ZnO-based hollow microspheres with mesoporous shells: Polyoxometalate-assisted fabrication, growth mechanism and photocatalytic properties

With the assistance of Keggin-type polyoxometalate, ZnO hollow microspheres with mesoporous shells were synthesized via a simple solvothermal approach without any templates and surfactants. The observations of morphology and structure performed by field emission scanning electronic microscopy and transmission electron microscopy indicated that the shells of the ZnO hollow spheres were built from nanosheets which were composed of nanoparticles. The transformation of structure and composition of samples were investigated by X-ray diffraction, X-ray photoelectron spectrometry and fourier transform infrared absorption spectroscopy. The formation mechanism of the hollow spheres is proposed based on time-dependent experimental results. The ZnO hollow microspheres exhibited a high photocatalytic activity for decolorization of Rhodamine B under ultraviolet irradiation.