纳米TiO2原位聚合硅丙复合乳液的制备

采用硅烷偶联剂对纳米二氧化钛进行表面处理,以改性纳米二氧化钛和有机硅中间体为种子乳液,以过硫酸钾为引发剂,甲基丙烯酸甲酯(MMA)、甲基丙烯酸丁酯(MBA)为主要共聚单体,通过原位聚合反应,合成纳米TiO2-硅丙复合乳液。采用红外光谱、透射电镜(TEM)、激光粒度分布等手段,对所制备的纳米TiO2-硅丙复合乳液进行了表征,证明所得产品是硅氧烷和丙烯酸酯的共聚物,具有核/壳结构,且乳液粒径分布较窄,平均粒径在63 nm左右。     

电沉积TiO_2纳米晶薄膜及其光电性能研究

采用阴极电沉积法在导电玻璃基体上制备了TiO2薄膜.运用扫描电子显微镜、X-射线能量散射分析仪和X-射线衍射仪对TiO2薄膜的形貌和结构进行了分析.以N719染料敏化的TiO2薄膜为阳极,0.5 mol/L KI和0.05 mol/L I2的乙氰和乙烯碳酸酯的混合溶液为电解液,碳电极为阴极,组成太阳能电池,通过电流-电压曲线研究了太阳能电池的性能.结果表明:TiO2薄膜的晶型为锐钛矿,其晶粒d平均为28.8 nm.太阳能电池的U开路为0.513 V,J短路为22.8 A/m2,填充因子为0.392,光电转换效率为0.466%.     

掺杂无机纳米粒子PVA复合改性香精微胶囊壁性能研究

采用原位聚合法, 以掺杂了金属Fe3+、Zr4+、Ce4+的二氧化钛（TiO2）纳米粒子及TiO2纳米粒子填充聚乙烯醇（PVA）改性三聚氰胺甲醛树脂（MF）为微胶囊复合壁材,橙花精油为芯材,制备了掺杂TiO2纳米粒子填充PVA改性囊壁的相变微胶囊。采用傅里叶变换红外光谱仪、热失重分析仪、扫描电子显微镜和透射电子显微镜研究了掺杂TiO2纳米粒子对微胶囊力学性能、热性能及表面形态的影响。结果表明,当囊壁中均匀地加入掺杂纳米TiO2后,芯材释放速率减小;当壁材中Fe3+掺杂纳米TiO2含量为0.5 %（质量分数,下同）时,微胶囊的破损率为18.1 %,芯材的10 d释放速率为4.5 %。     

恒电流法制备Cu2O/TiO2复合纳米管阵列异质结光电极

通过在含F-离子的电解液中阳极氧化Ti薄片基底制备了TiO2纳米管阵列,随后通过恒电流沉积的方法在在TiO2纳米管阵列顶部原位电沉积了Cu2O纳米颗粒。场发射电子扫描显微镜显示TiO2纳米管这列被成功制备,通过恒电流电化学沉积后,TiO2纳米管阵列顶部出现大量纳米颗粒物质,并且随着沉积时间的延长,可以控制沉积物的量。通过X-射线衍射谱的特征衍射谱图我们可以发现TiO2锐钛矿的衍射峰以及相对较弱的Cu2O衍射峰,这说明Cu2O晶体的结晶度不高。在能谱（EDS）图中我们可以发现Ti、Cu、O三种元素,结合XRD以及FE-SEM结果我们可以指出,通过恒电流法确实可以在TiO2纳米管阵列顶部原位沉积Cu2O纳米颗粒。     

A Novel Gel Electrolyte Based on Polyurethane for Highly Efficient in Dye-sensitized Solar Cells

A structurally interconnected block copolymer was facilely prepared by the polymerization of poly(oxyethylene)-segmented diol (PEG2000 and PPG1000) and Isophorone diisocyanate (IPDI), followed by a late-stage curing to generate urethane group cross-linked gels. The gel structure, with multiple functionalities including poly(oxyethylene) segments and urethane linkers were characterized by Fourier transform infrared spectroscopy. The gel-like copolymer was used to absorb a liquid electrolyte; formation of 3D interconnected nanochannels, as could be observed by field emission scanning electronic microscopy has confirmed this absorption of the liquid electrolyte by the copolymer. This elastomeric copolymer was used as the matrix of a polymer gel electrolyte (PGE) for a dye-sensitized solar cell (DSSC), which shows extremely high photovoltaic performance (soaking for 1 h in the electrolyte). In particular, the PGE containing 65 wt% of the liquid electrolyte renders a power conversion efficiency of 7.68 % for its DSSC, with a short-circuit photocurrent density of 16 mA cm^?2, an open-circuit voltage of 0.73 V, and a fill factor of 0.65. Electrochemical impedance spectra, and dark current measurements were used to substantiate the explanations of the photovoltaic parameters.     

SEM study of the growth of electrochemically obtained polyselenophene thin films. Effect of electrolyte and monomer concentration in acetonitrile

Summary The influence of electrolyte and monomer concentration on properties and morphology of electrochemically obtained polyselenophene films doped and undoped with hexafluorophosphate and tetrafluoroborate anions was analyzed. The films were deposited on SnO₂-coated glass in a classical three-electrode cell from the monomer and the electrolyte in anhydrous acetonitrile.The electrochemical growth of polyselenophene thin films was studied by X-ray photoelectron spectroscopy (XPS), electron probe microanalysis (EPMA), and scanning electron microscopy (SEM). The morphology study revealed different three- dimensional (3D) and bidimensional (2D) growth, depending on monomer and electrolyte concentration.     

Nanostructure of buried interface layers in TiO₂ anatase thin films grown on LaAlO₃ and SrTiO₃ substrates

TiO(2) anatase thin films grown by pulsed laser deposition are investigated by high resolution transmission electron microscopy and high angle annular dark field scanning transmission electron microscopy. The analyses provide evidence of a peculiar growth mode of anatase on LaAlO(3) and SrTiO(3) characterized by the formation of an epitaxial layer at the film/substrate interface, due to cationic diffusion from the substrate into the film region. Pure TiO(2) anatase growth occurs in both specimens above a critical thickness of about 20 nm. The microstructural and chemical characterization of the samples is presented and discussed in the framework of oxide interface engineering.     

凝胶-溶胶法制备纳米二氧化钛的pH控制

利用凝胶-溶胶法制备纳米二氧化钛，采用透射电镜（TEM）和X射线衍射（XRD）对产物进行了表征，考察了体系pH变化和电解质（高氯酸钠）对它的影响，以及初始pH（pH0）对二氧化钛形貌及体系组成的影响。结果表明，产物为锐钛矿型二氧化钛，平均粒径5～15nm；体系pH变化是由于OH^-（或H^＋）在氢氧化钛或二氧化钛表面的吸附和脱附，添加0．1mol／L高氯酸钠能促进OH^-（或H^＋）的吸附和脱附过程。pH0显著影响二氧化钛形貌和体系组成，pH0=1．0时为球状晶体，pH0=9．4时为较规则的立方晶体，至pH0=11．5变为椭球形。pH0〉9．4时，二氧化钛物质的量分数显著下降，至pH0=12．0时无二氧化钛生成，因此应控制pH0〈9．4。     

Formation mechanism and packing options in tubular anodic titania films

Titania nanotube arrays were synthesized via anodic oxidation of titanium foils in glycerol electrolyte containing NH₄F at anodization voltage ranging from 10 V to 30 V. The structural parameters of self-organized periodic arrays of titania nanotubes were determined by small-angle neutron scattering and scanning electron microscopy techniques. Transmission electron microscopy and electron diffraction studies of single-standing nanotubes revealed the presence of nanocrystalline titanium oxide phases with oxidation states lower than +4 (TiO, Ti₂O₃). Several assumptions on growth and self-organization mechanism of nanotube arrays have been made.     

Preparation, characterization and photocatalytic behavior of WO3-fullerene/TiO2 catalysts under visible light

WO3-treated fullerene/TiO2 composites (WO3-fullerene/TiO2) were prepared using a sol-gel method. The composite obtained was characterized by BET surface area measurements, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, transmission electron microscopy, and UV-vis analysis. A methyl orange (MO) solution under visible light irradiation was used to determine the photocatalytic activity. Excellent photocatalytic degradation of a MO solution was observed using the WO3-fullerene, fullerene-TiO2, and WO3-fullerene/TiO2 composites under visible light. An increase in photocatalytic activity was observed, and WO3-fullerene/TiO2 has the best photocatalytic activity; it may attribute to the increase of the photo-absorption effect by the fullerene and the cooperative effect of the WO3.     

三维网状结构TiO_2纳米管的制备及光电性能研究

采用阳极氧化法在钛网基底上制备出三维网络结构的TiO_2纳米管。研究了电解液浓度、电解时间、电压及含水量等参数对TiO_2纳米管形貌的影响。利用扫描电子显微镜、能量色散X-射线光谱仪、X-射线衍射仪及紫外-可见漫反射光谱对其形貌和结构进行表征和分析,并通过光电流信号对TiO_2纳米管的光电性能进行研究。结果表明,当乙二醇溶液中氟化铵质量分数为0.5%,水为10%,U为40 V,t为2 h时制备的TiO_2纳米管的形貌最完整,结构最有序,并且具有良好的紫外-可见光响应性。     

Conducting polymers of terepthalic acid bis-(2-thiophen-3-yl-ethyl) ester and their electrochromic properties

Terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester (TATE) was synthesized through the reaction of 2-thiophen-3-yl-ethanol and terepthaloyl chloride. Homopolymer of TATE was synthesized via potentiostatic and potentiodynamic methods by using tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte in dichloromethane/borontrifluoride ethylether solvent mixture (DM/BFEE) (8:2, v/v). Copolymerisation of TATE with thiophene was achieved in DM/BFEE solvent mixture (8:2, v/v) by using TBAFB as the supporting electrolyte in the presence of thiophene. The chemical structure of monomer is characterised via NMR and FTIR. Both homopolymer (PTATE) and copolymer P(TATE-co-Th) were characterised by various techniques including cyclic voltammetry, FTIR, scanning electron microscopy and UV-VIS spectroscopy. Conductivities of samples were measured by four probe technique. Optoelectrochemical analysis indicates that the homopolymer and copolymer have an electronic band gap, measured as the onset of the π-to-π* transition, as 2.17 and 2.00 eV, respectively.     

PET/纳米TiO2抗紫外纤维的制备及性能研究

将金红石型TiO2添加至聚合反应体系中进行原位聚合,得到PET／纳米TiO2复合材料,通过透射 电镜(TEM)、扫描探针显微镜(SPM)研究了纳米TiO2在PET基体中的分散情况。将复合材料纺制成纤维, 并进行了力学性能、抗紫外性能等测试。结果表明,金红石型TiO2在基体中分散较均匀,TiO2质量分数为 1％时,基本呈纳米尺寸分散;PET／纳米TiO2纤维中含1％TiO2时,断裂强度较纯PET纤维下降6％左右,断 裂伸长率、结晶度也有所下降。织物对UVA,UVB波段的紫外线具有优异的屏蔽效果,抗紫外因子(UPF 值)可达50以上。     

N-Ion-implanted TiO2 photoanodes in quantum dot-sensitized solar cells

Hierarchical nanostructured titanium dioxide (TiO(2)) clumps were fabricated using electrostatic spray with subsequent nitrogen-ion doping by an ion-implantation technique for improvement of energy conversion efficiency for quantum dot-sensitized solar cells (QDSCs). CdSe quantum dots were directly assembled on the produced N-ion-implanted TiO(2) photoanodes by chemical bath deposition, and their photovoltaic performance was evaluated in a polysulfide electrolyte with a Pt counter electrode. We found that the photovoltaic performance of TiO(2) electrodes was improved by nearly 145% upon N-ion implantation. The efficiency improvement seems to be due to (1) the enhancement of electron transport through the TiO(2) layer by inter-particle necking of primary TiO(2) particles and (2) an increase in the recombination resistance at TiO(2)/QD/electrolyte interfaces by healing the surface states or managing the oxygen vacancies upon N-ion doping. Therefore, N-ion-doped photoanodes offer a viable pathway to develop more efficient QD or dye-sensitized solar cells.     

二氧化钛包裹碘单质(I_2/TiO_2)制备及其光催化降解苯酚

采用水热法,以Ti(SO4)2为钛源,KIO3为掺碘剂制备了具有高可见光活性,高稳定性的二氧化钛包裹碘单质(I2/TiO2)光催化剂.利用X射线光电子能谱(XPS)、X射线晶体粉末衍射(XRD)、透射电子显微镜(TEM)和紫外可见漫反射光谱(DRS)等表征手段对样品进行表征.结果表明,I2/TiO2中除含有锐钛矿相二氧化钛外、还含有碘单质和碘酸;I2/TiO2粒径大小为45 nm左右;在波长384 nm至700 nm范围内,该催化剂有强烈的吸收.探讨了该催化剂的形成过程和可见光催化机理.以苯酚降解反应为探针,测定了I2/TiO2光催化活性.结果显示:在全谱光源照射下I2/TiO2活性略高于P25,在可见光范围内其活性是P25的3倍多.确定了降解苯酚的最佳条件:全谱光源照射,投加量为0.5 g/L,苯酚浓度大于10 mg/L,溶液pH为3.2.I2/TiO2重复使用4次后,催化活性没有明显下降.     

Cu掺杂二氧化钛纳米管阵列的研究

范围内,有助于提高TiO2纳米管阵列对可见光的利用效率.     

尖晶石锰酸锂的表面包覆改性研究

采用溶胶凝胶法在尖晶石锰酸锂的表面包覆一层二氧化钛,并通过扫描电镜对包覆前后样品的粒径和形貌进行了表征。电化学测试结果表明：二氧化钛包覆层能有效减少锰酸锂和电解液的直接接触,减少锰的溶解,提高材料的电化学稳定性。当二氧化钛包覆量为2%（质量分数）时,样品具有最好的电化学性能,在55 ℃下1 C充放电循环首次放电比容量为111.4 mA·h/g,循环50次后仍具有101.5 mA·h/g的比容量。     

常压液相法一步合成铌掺杂二氧化钛

采用四氯化钛为钛源,常压下在离子液体（1-乙基-3-甲基咪唑四氟化硼酸盐）中一步合成掺杂铌的二氧化钛粉末。采用X射线衍射、扫描电子显微镜、紫外–可见漫反射光谱对产物的结晶、掺杂、表面形貌进行表征,并测试了掺杂量的改变对光吸收性及表观介电常数的影响。结果表明：制备的掺杂TiO2粉末为锐钛矿晶型且结晶完善;Nb5＋掺杂使粉末光吸收带边发生蓝移;掺杂后粉末的介电常数增大,当掺杂Nb量为5%（摩尔分数）时表观介电常数达到最高值。     

酚醛树脂基高度有序介孔炭材料的合成及其电容性

以碱性条件下制备出的A阶酚醛树脂为炭前驱体,三元嵌段共聚物P123及F127为介孔模板剂,采用乙醇溶剂蒸发诱导自组装与程序升温策略,制备出高度有序、比表面积达550.12 m2/g、孔容为0.385 4 cm3/g、平均孔径为3.97 nm的酚醛树脂基有序介孔炭材料。利用小角X射线衍射、扫描电镜、透射电镜、物理吸附及电化学性能测试等技术,研究了不同合成条件下得到的有序介孔炭材料的结构和电化学性能。结果表明,在6 mol/L KOH电解质溶液的三电极体系中,该优化有序介孔炭材料在1 A/g的电流密度下比电容可达146.5 F/g。     

Effects of acid on the microstructures and properties of three-dimensional TiO2 hierarchical structures by solvothermal method

ABSTRACT: Three-dimensional (3D) TiO2 hierarchical structures with various microstructures have been successfully synthesized via a surfactant-free and single-step solvothermal route, in which hydrochloric acid (HCl), nitric acid (HNO3), and acetic acid (HAc) are employed as the acid medium, respectively. The effects of acid medium on the microstructures and properties of 3D TiO2 hierarchical structure have been studied. The results indicate that 3D dandelion-like microspheres assembled of radial rutile nanorods are obtained in the sample prepared with HCl. Both the fraction of rutile and the diameter of nanorod enhance with the increasing HCl concentration. For the products derived from either HNO3 or HAc, 3D spheres composed of anatase nanoparticles are present. The 3D dandelion-like TiO2 hierarchical structures show low reflectance and efficient light harvesting since this ordered rod geometry offers a light-transfer path for incident light as well as multiple reflective and scattering effects. Moreover, 3D TiO2 with this unique topology shows superior photocatalytic activity despite low surface area, which can be ascribed to the enhanced light harvesting, fast electron transport, and low electron/hole recombination loss.