PS/TiO2核壳型微球和空心TiO2微球有序排列的制备

利用纳米级二氧化钛（TiO₂）溶胶微粒与聚苯乙烯（PS）胶体颗粒的混合悬浮液,以垂直共沉积的方法制备了核壳型PS/TiO₂微球的有序排列。当利用煅烧的方法去除PS胶粒晶体模板后,可以形成空心TiO₂微球的三维有序排列。考察了混合悬浮液中两种胶体颗粒的体积比（PS∶TiO₂=R）对空心TiO₂微球有序排列形成的影响。实验结果表明,合适的R值（6∶1）对于空心微球有序排列的形成至关重要。与此同时,浸渍填充法对照实验的结果表明,煅烧过程中TiO₂纳米颗粒晶型转化引起的收缩是造成TiO₂空心球产生的主要原因。     

水热法制备CdS/TiO2及其光活性

研究了CdS/TiO₂光催化的耦合效应.以TiO₂、CdCl₂和Na₂S为原料在200 ℃、6 h水热反应条件下一次合成CdS含量不同的CdS/TiO₂,通过XRD、SEM、EDS和IR对样品进行表征,并通过谢乐公式（Scherrer equation）估算出样品晶粒的粒径.XRD图表明CdS/TiO₂为锐钛矿型TiO₂、立方相和六方相CdS的混合相.SEM表明CdS粒径为20～50 nm,TiO₂粒径为50～100 nm.通过罗丹明B(rhodamine B)光降解脱色,表征了样品的光活性,结果表明当CdS∶TiO₂为1.0时,CdS/TiO₂开始出现耦合效应,当CdS∶TiO₂为1.5时,CdS/TiO₂的光活性最强,在30 min内紫外光降解4 mg•L^-1罗丹明B溶液的降解率达74.3%.     

反相微乳液法制备TiO2/ZrO2复合陶瓷膜

研究了采用反相微乳液法制备TiO₂/ ZrO₂复合微乳液,并以其作为前体制得TiO₂/ ZrO₂复合膜。通过对复合微乳液的透射电镜测试,结果表明TiO₂/ ZrO₂复合微粒在油相包裹的“水池”中生成。由扫描电子显微镜观察到TiO₂/ ZrO₂复合膜表面微粒以棒状形式分布,而且复合膜对大肠杆菌的灭菌率达98 %～99 %。     

用相转移法有机表面改性纳米TiO2

以正辛基三乙氧基硅烷（LM-N308）为有机表面改性剂,用相转移法对金红石相纳米TiO₂进行有机表面改性。采用了傅里叶变换红外光谱（FTIR）、热分析（TG-DTA）、X 射线光电子能谱（XPS）、高分辨透射电镜（HRTEM）、亲油化度实验等对所得的纳米TiO₂进行了表征。红外光谱和X射线光电子能谱表明LM-N308以化学键合的方式结合在纳米TiO₂表面。HRTEM结果显示,在纳米TiO₂的表面存在厚度均匀约2 nm的有机包覆层。TG和亲油化度实验数据表明,纳米TiO₂表面化学吸附的LM-N308的饱和质量分数为7.0%～9.7%。分散性实验表明,经LM-N308表面改性的纳米TiO₂由亲水性变成了疏水性。     

镍掺杂对二氧化钛光催化性能影响的研究

采用溶胶-凝胶法制备了纳米二氧化钛以及不同掺镍量的TiO₂纳米粒子(原料中Ni∶TiO₂的摩尔分数为1%、3%、5%、7%、9%)。用紫外光照射甲基橙溶液的光催化降解实验研究了掺镍对二氧化钛光催化剂催化效率的影响，试验结果表明,当用n（Ni）∶n（TiO₂）＝5%的Ni(NO₃)₂溶液进行镍掺杂时，制得的TiO₂催化剂光催化效率最高，但与纯TiO₂相比，镍掺杂会减弱TiO₂的光催化效率。X射线衍射分析表明，未掺杂的TiO₂以锐钛矿和金红石两种晶型混合存在，镍掺杂后TiO₂的晶型几乎全为锐钛矿。镍掺杂后会减小TiO₂粒子的尺寸，增大其比表面积。     

用二维FTIR研究纳米TiO2改性丝素蛋白聚集态结构转变

采用溶胶-凝胶方法制备纳米TiO₂复合丝素膜。UV和SEM测试结果表明,该丝素膜中纳米TiO₂均匀分散在丝素中,TiO₂粒径约为80 nm;同时采用一维红外光谱、二维红外相关光谱对纯丝素膜及复合丝素膜结构进行表征。结果表明,随着纳米TiO₂的生成,丝素蛋白中弱氢键缔合的N—H键以及自由的N—H键发生断裂及重组,生成了强氢键;丝素分子从无序状态转变为有序排列,同时无规线团构象及α螺旋构象向β折叠构象发生转变,最后促使丝素蛋白的结晶构象从Silk Ⅰ转变为Silk Ⅱ。     

用二维FTIR研究纳米TiO2改性丝素蛋白聚集态结构转变

采用溶胶-凝胶方法制备纳米TiO₂复合丝素膜。UV和SEM测试结果表明,该丝素膜中纳米TiO₂均匀分散在丝素中,TiO₂粒径约为80 nm;同时采用一维红外光谱、二维红外相关光谱对纯丝素膜及复合丝素膜结构进行表征。结果表明,随着纳米TiO₂的生成,丝素蛋白中弱氢键缔合的N—H键以及自由的N—H键发生断裂及重组,生成了强氢键;丝素分子从无序状态转变为有序排列,同时无规线团构象及α螺旋构象向β折叠构象发生转变,最后促使丝素蛋白的结晶构象从Silk Ⅰ转变为Silk Ⅱ。     

发泡剂对空心石英玻璃微球结构的影响

空心玻璃微球因具有低密度、高强度、耐高温等优点而被广泛研究。采用喷雾造粒法与粉末法相结合,掺入发泡剂,以射频等离子体作为热源制备空心石英玻璃微球,研究了SiC、CaSO₄、CaCO₃三种发泡剂对制备空心石英玻璃微球的影响。结果表明,通过喷雾造粒法将发泡剂与SiO₂充分混合形成粗坯颗粒,再利用射频等离子设备对粗坯粉末进行高温烧结,得到空心石英玻璃微球。其中CaSO₄、CaCO₃发泡剂效果较差,所产生的气体难以留在玻璃微球内部形成中空气泡;而SiC发泡剂效果最好,在射频等离子烧结过程中产生气体,被玻璃液包裹形成空心结构,得到的玻璃微球平均真密度为1.799 5 g/cm³。选用菲利华石英块状疏松体作为SiO₂原料,当m(SiO₂)∶m(SiC)∶m(H₂O)为100∶3∶300时,可制备出平均真密度为0.72 g/cm³的空心多孔石英玻璃微球。     

ZrO2(3Y)包裹Al2O3纳米复合粉体的制备

以pH值缓冲溶液为沉淀剂,用非均匀成核和液相共沉淀相结合的方法合成出了ZrO₂（3Y）包裹Al₂O₃纳米复合粉体.用XRD、TEM对所制备粉体进行了表征.研究表明：加入分散剂使Al₂O₃悬浮液的等电点向酸性区移动,Zeta电位绝对值增大,其中pH值为9.56对应的Zeta电位绝对值最大,悬浮液最稳定.Al₂O₃悬浮液pH值为9.5,ZrOCl₂和YCl₃混合溶液浓度为0.2 mol•L^-1时前驱体的收得率最高.600℃煅烧后得到的粉体中只有α-Al₂O₃、t-ZrO₂两种物相,在Al₂O₃颗粒表面附着10 nm左右的ZrO₂（3Y）颗粒.     

SnO2中空微球的制备与气敏性能

在不加任何表面活性剂情况下,采用磺化的聚苯乙烯（PS）微球为模板,二水结晶二氯化锡（SnCl₂·2H₂O）为锡源,成功制得SnO₂中空微球。利用X射线衍射仪（XRD）、扫描电镜（SEM）、高分辨透射电镜（HRTEM）和氮气吸附脱附仪（BET）对材料的结构和形貌进行了表征,研究并讨论了温度、乙醇浓度等因素对SnO₂纳米颗粒及SnO₂中空微球气敏性能的影响。结果显示,SnO₂中空微球的比表面积为48.49m²/g,比SnO₂纳米颗粒的比表面积（21.94m²/g）提升了1.21倍。比表面积增加有助于SnO₂材料表面吸附更多被测气体以提升表面化学反应,进而提升气敏性能。在260℃下,SnO₂中空微球对200μL/L乙醇的灵敏度为66.26,与SnO₂纳米颗粒相比（51.34）,气敏性能提高了0.29倍。     

细乳液聚合制备二氧化钛/聚苯乙烯复合微球及其形貌分析

采用细乳液聚合法,以γ-甲基丙烯酰氧基丙基三甲基硅烷改性的TiO2粒子为核,制备了核壳结构的TiO2/聚苯乙烯(PS)复合微球。研究了超声细乳化时间、乳化剂十二烷基硫酸钠(SDS)的浓度、TiO2用量对细乳液粒径及其分布的影响。通过纳米粒度与Zeta电位分析仪、红外光谱、透射电镜等分析手段对产物进行了表征。结果表明,随着超声细乳化时间的增加,初始液滴的粒径变小。聚合后的乳胶粒粒径随着SDS浓度的增大而减小;TiO2用量不足导致乳胶粒粒径分布变宽,且出现双峰;制备所得的TiO2/PS复合微球粒度分布较为均匀,平均直径为176.5 nm,球形规整度较好。     

Preparation of polystyrene/zirconia core-shell microspheres and zirconia hollow shells

Zirconia/polystyrene core-shell microspheres were prepared through room-temperature aging process and a solvothermal process with ethanol as solvent. Through the hydrolysis of zirconium propoxide, ZrO₂ was coated on PS cores to form the core-shell microspheres. And hollow ZrO₂ shells were formed by calcining the core-shell particles in a muffle oven under static air at 600 °C.     

Preparation of Various Composite TiO 2 /SiO 2 Ultrafine Particles by Vapor-Phase Hydrolysis

Ultrafine TiO 2 /SiO 2 composite particles were prepared by vapor-phase simultaneous hydrolysis of titanium tetraisopropoxide (TTIP) and tetraethoxyorthosilicate (TEOS). The various modes of TiO 2 /SiO 2 composite particles, including both core-shell and mixed-type structures, were prepared according to the methods of reactant mixing. They differed considerably in morphology, size, chemical composition, and crystal structure evolution by heat treatment. In a mixed-type composite of TiO 2 and SiO 2 , SiO 2 inhibited both the growth of the particles and the anatase-to-rutile transformation of TiO 2 .     

优化制备粒度均匀分布的Ce-Cu/TiO2空心微球及其光-显性能

以Ce(NO3)3?6H2O和Cu(NO3)2?3H2O为改性剂制备Ce–Cu/TiO2空心微球，通过均匀设计与BP神经网络模型优化Ce–Cu/TiO2空心微球的制备工艺参数。用激光粒度分析仪对Ce–Cu/TiO2空心微球的粒度分布进行测试，用SEM和TEM对Ce–Cu/TiO2空心微球的微观形貌进行表征，用比表面积及孔径测定仪对Ce–Cu/TiO2空心微球的孔结构进行测试，采用等温吸放湿法对粒度均匀分布的Ce–Cu/TiO2空心微球的湿性能进行测试，用紫外–可见分光光度计测试其光性能。结果表明，粒度均匀分布的Ce–Cu/TiO2空心微球制备工艺参数为：磁力搅拌速度VMS=910 r/min、溶液B加入溶液A的速度VAB=1.32 mL/min、溶液D加入溶液C的速度VCD=0.86 mL/min、煅烧升温速度VTC=2.47℃/min和煅烧温度TC=485℃，所制空心微球d10=103.74 nm，d50=141.46 nm和d90=188.84 nm，粒径分布区间d90–d10为85.10 nm，空心微球具有良好的光–湿性能，1~6 h对甲醛气体的降解率为21.6%~53.9%，相对湿度32.28%~84.34%的平衡含湿量为0.0364~0.2746 g/g。     

Controlling Shell Thickness of PS/SiO2 Core-Shell Particles and Their Crystallization into 3-D Ordered Thin Film

PS/SiO2 particles with core-shell structure were synthesized by coating silica on surface of polystyrene (PS)colloidal particles. The reaction parameters, such as initial tetraethyl orthosilicate (TEOS) concentration, water concentration and reaction temperature, have been investigated to control the thickness of silica shells. The shell thickness was prepositional to the square root of the initial concentration of TEOS and first increased with increasing water concentration, reached a maximum at about 2.0 mol/L and then started decreasing beyond that concentration. It was also found that the shell thickness decreased firstly with the reaction temperature added, then tended to a constant. The so-synthesized PS/SiO2 core-shell particles were directly crystallized into 3-D ordered thin film, then sintered at 570 ℃ into the ordered macroporous thin film.Compared with the conditional method, the present approach avoids repeatedly filling the precursor in the templetes and save time more.     

Fabrication of size-controllable Fe2O3 nanoring array via colloidal lithography

Tailed-Fe(2)O(3) ring arrays are fabricated by solution-dipping on a colloidal monolayer template. The influence of synthesis parameters on the quality of nanostructures has been investigated. The ring size can be controlled by changing the precursor concentration and varying the annealing time of the polystyrene sphere colloidal monolayer. In addition, the edge of the rings is sensitive to the surface tension of precursor solution, and high quality ordered ring arrays can be obtained by tuning the surface tension. This strategy allows the fabrication of specific metal oxides ring arrays with high quality and uniform morphology.     

Carbonization of PAN grafted uniform crosslinked polystyrene microspheres

Micrometer-sized polystyrene/poly(styrene-divinylbenzene) and polystyrene/polydivinylbenzene composite particles of narrow size distribution were formed by a single-step swelling process of uniform polystyrene template particles with emulsion droplets of dibutyl phthalate containing benzoyl peroxide and divinylbenzene in the presence or absence of styrene, followed by polymerization of the monomer(s) within the swollen template particles at 70 °C. Porous poly(styrene-divinylbenzene) and polydivinylbenzene uniform microspheres were formed by dissolution of the polystyrene part of the former composite particles. Hydroperoxide conjugated microspheres were formed by ozonolysis of the former porous microspheres. Uniform poly(styrene-divinylbenzene)/PAN and polydivinylbenzene/PAN core/shell microspheres were prepared by room temperature redox graft polymerization of AN onto the hydroperoxide conjugated particles. Uniform carbon microspheres were prepared by carbonization of the core/shell particles at 800 and 1100 °C under dynamic N₂ atmosphere. On the other hand, a similar treatment of the core particles only resulted in destruction of the particle shape. Carbon microspheres of increasing surface area (up to ca. 1000 m²/g) were prepared by activation of the former carbon microspheres with CO₂ at 850 °C. The influence of the carbonization temperature of the core/shell particles and the activation time of the carbon particles on the carbon yield and surface area has been elucidated.     

纳米光催化剂TiO_2/Fe_3O_4的制备及表征

采用两步法制备磁性负载纳米光催化剂TiO2/Fe3O4。首先用液相共沉淀法制备磁性纳米Fe3O4颗粒;然后用溶胶-凝胶法,以钛酸四正丁酯为先驱体,通过水解缩聚在Fe3O4纳米颗粒表面包覆TiO2层,得到易于磁分离回收的复合纳米光催化剂TiO2/Fe3O4,粒径大约为30 nm。利用TEM、XRD、FT-IR、VSM对Fe3O4和TiO2/Fe3O4的结构和性能进行了表征,结果表明,制备的Fe3O4为面心立方晶体(FCC)结构,具有超顺磁性;TiO2为锐钛矿相,包覆在Fe3O4的表面,形成了核-壳式结构的TiO2/Fe3O4复合光催化剂。     

不同聚苯乙烯微球的磺化

胶体颗粒是研究凝聚态物理性质、生命物质组装的理想模型体系,对胶体颗粒的研究具有十分重要的理论价值。聚苯乙烯(PS)微球是目前应用最为广泛的胶体粒子,由于其在合成过程中粒径可控且形貌均匀,因此,受到了越来越多的关注。文章制备了未交联的和交联的2种PS微球,研究了磺化时间对这2种PS微球的Zeta电势和粒径的影响。结果表明,在一定的反应时间内,未交联PS微球的Zeta电势和粒径,随磺化时间增加至原粒径的2.5倍,最后溶解。交联PS微球的Zeta电势和粒径随磺化时间增加至原粒径的5.5倍,但不溶解,而是形成C型胶体粒子。掌握了聚苯乙烯微球的磺化规律,可以得到尺寸及带电量不同的磺化聚苯乙烯,对凝聚态的物理性质的等研究具有重要意义。