Cl2／TiCl4体系引发IBVE活性阳离子聚合的研究（Ⅰ）：引…

采用ＵＶ光谱法证明了ＩＢＶＥ／Ｃｌ２／ＴｉＣｌ４／甲苯聚合体系中同时存在着两种引发活性中心及络合竞争，研究了Ｃｌ２／ＴｉＣｌ４和Ｈ２Ｏ／ＴｉＣｌ４络合平衡，求出了２０℃时２ＴｉＣｌ４←Ｃｌ２和ＴｉＣｌ４←Ｈ２Ｏ络合平衡不稳定常数。     

Grignard试剂同6,6—二烷基富烯反应的研究

烯丙基卤化镁和环戊二烯基溴化镁同６，６－二烷基富烯分别进行富烯环外双键的加成和还原反庆，生成的取代环戊二烯基负离子用（ＣｐＴｉＣｌ２）２Ｏ（Ｃｐ＝环戊二烯基）或ＴｉＣｌ４配合，合成式为Ｃｐ（Ｃ６Ｈ４－ＣＲＲ＾１－ＣＨ２Ｃｈ－ＣＨ２）ＴｉＣｌ２和（Ｃ６Ｈ４ＣＨＲＲ＾１）２ＴｉＣｌ２的化合物，对烯丙基卤化镁、环戊二烯基溴化镁同富烯的反应机理进行了探讨。     

TiO2陶瓷顶层膜的化学气相淀积生长研究

以ＴｉＣｌ和Ｔｉ（ＯＣ４Ｈ９）４为源物质采用热化学气相淀只（ＣＶＤ）法及射频ＰＣＶＤ法在多孔α－Ａｌ２Ｏ３陶瓷衬底上淀积生长ＴｉＯ２薄膜，观测ＴｉＯ２膜的生长方式、生长速率以及结构和表面形貌等，讨论其生长机制，评价ＣＶＤ改性生长的顶怪ＴｉＯ２陶瓷膜的气体渗透性。     

Ce2O—TiO2／SiO2的制备及除氟性能研究

以ＳｉＯ２为基质，ＣｅＯ２ＴｉＯ２为包覆物质，采用溶胶凝胶法制备ＣｅＯ２ＴｉＯ２／ＳｉＯ２表面复合物，并对所制复合物进行除氟测试。用扫描电镜（ＳＥＭ）观察表面形貌，讨论实验环境、试剂用量等因素对ＣｅＯ２ＴｉＯ２／ＳｉＯ２制备及除氟性能的影响，结果表明：ｎＴｉ（ＯＣ４Ｈ９）４／ｎＣｅＣｌ３·７Ｈ２Ｏ＝１、ｎＣＨ３ＣＯＯＨ／ｎＴｉ（ＯＣ４Ｈ９）４＝４５、ｎＣ３Ｈ８Ｏ３／ｎＴｉ（Ｏ４Ｈ９）４＝０３、ＲＨ＝９５％，热处理温度１１０℃时，所制ＣｅＯ２ＴｉＯ２／ＳｉＯ２对Ｆ－的吸附容量（ｑ）为２１４ｍｇ／ｇ，去除率（Ｅ）为８５６％。     

Grignard试剂同6，6－二烷基富烯反应的研究

烯丙基卤化镁和环戊二烯基溴化镁同６，６－二烷基富烯分别进行富烯环外双键的加成和还原反应，生成的取代环戊二烯基负离子用（ＣｐＴｉＣｌ＿２）＿２Ｏ（Ｃｐ＝环戊二烯基）或ＴｉＣｌ４配合，合成通式为Ｃｐ（Ｃ＿５Ｈ＿１－ＣＲＲ￣１－ＣＨ＿２ＣＨ＝ＣＨ＿２）ＴｉＣｌ＿２和（Ｃ＿５Ｈ＿４ＣＨＲＲ￣１）＿２ＴｉＣｌ＿２的化合物。对烯丙基卤化镁、环戊二烯基溴化镁同富烯的反应机理进行了探讨。     

Co－Mo／TiO_2和C0－M0／γ－Al_2O_3加氢脱硫催化剂的研究

本文考察了ＣｏＭｏ／ＴｉＯ３和ＣｏＭｏ／γ－Ａｌ２Ｏ３催化剂的加氢脱硫性能及表面结构变化和预处理条件对其活性的影响．担体ＴｉＯ２（Ａ）和ＴｉＯ２（Ｂ）分别采用ＴｉＣｌ４中和法和ＴｉＯＳＯ４水解法制备．结果表明，催化剂的活性顺序为ＣｏＭｏ／ＴｉＯ２（Ａ）＞ＣｏＭｏ／ＴｉＯ２（Ｂ）＞ＣｏＭｏ／γ－Ａｌ２Ｏ３催化剂的预处理条件对催化剂的加氢脱硫（ＨＤＳ）和加氢（ＨＹＤ）活性有很大影响，ＴｉＯ２担体上Ｍｏ物种主要以八面体配位构型存在，Ｍｏ６＋更易于还原成低价态．     

α-氯代乙苯/TiCl4/Ti(OiPr)4引发β-蒎烯活性阳离子聚合

－４０℃条件下,在ＣＨ２Ｃｌ２溶剂中以α－氯代乙苯为引发剂,ＴｉＣｌ４和Ｔｉ（ＯｉＰｒ）４混合物为Ｌｅｗｉｓ酸活化剂,进行β－蒎烯阳离子聚合,单独使用强的Ｌｅｗｉｓ酸ＴｉＣｌ４时,聚合反应在瞬间完成,聚合产物的分子量分布较宽,添加本身无催化活性的弱Ｌｅｗｉｓ酸Ｔｉ（ＯｉＰｒ）４后,聚合反应减缓且聚合产物的分子量的分布变窄,当Ｔｉ（ＯｉＰｒ）４／ＴｉＣｌ４摩尔比为１／３时,产物的分子量随单体转化率线性增加,且分子量分布较窄,显示出活性聚合特性这种活性聚合特性由单体添加实验进一步得到证实。     

高活性的茂基钛配合物／正丁基锂加氢催化体系的研究

考察了茂环上不同取代基及钛上阴离子配体对茂基钛配合物／正丁基锂催化体系加氢活性和稳定性的影响。在充分发挥该体系催化活性的条件下，由配合物Ｃｐ２ＴｉＣｌ２、Ｃｐ２ＴｉＦ２和Ｃｐ２Ｔｉ［ＯＣ６Ｈ３（ＣＨ３－２）Ｃｌ－４］２组成的催化体系对辛烯－１加氢的最高活性（或初活性）达到４６￣５８ｓ＾－１。     

不锈钢钝化膜在醛化液中自钝能力的研究

采用电偶极化和恒电位极化等电化学方法,评价１Ｃｒ１８Ｎｉ９Ｔｉ不锈钢阳极钝化膜和ＳＵＳ３６不锈钢原始钝化膜在７０℃的维尼维醛化液｛Ｈ２ＳＯ４（２４０ｇ／ｌ＋Ｎａ２ＳＯ４（７０ｇ／ｌ）＋ＨＣＨＯ（２５ｇ／ｌ）＋「Ｆｅ＾３＋」（３５．４＊１０＾－６）＋「Ｃｌ＾－」（２４０ｍｇ／ｌ）｝中的自钝能力,探讨醛化液组分、Ｆdisplay status     

FTIR研究聚丙烯负载型催化剂的的制备过程

采用红外光谱跟踪分析用于丙烯聚合的ＭｇＣｌ２负载型催化剂的制备过程,阐明了制备过程中的主要化学变化。认为载体ＭｇＣｌ２含水对催化剂负载过程及钛含量有极大的影响。ＭｇＣｌ２的溶解是一经过中间过渡态的醇化过程,邻苯二甲酸酐不仅会与部分醇反应生成酯,而且还与水反应生成酸,起了除水的作用;其中酯在ＴｉＣｌ４负载中作为内酯,酸容量与－Ｍｇ－（ＯＲ）作用生成Ｍｇ（ＯＨ）２或Ｍｇ（ＯＨ）Ｃｌ;在负载过程中,Ｔｉ     

STS study of TiO2 film and Pt-deposited TiO2 film in air

Direct investigation of the electronic structure of catalyst surfaces on the near-atomic scale in general has not been impossible in the past. However, with the advent of the scanning tunneling microscope (STM), the opportunity arises for incorporating the scanning tunneling spectroscopy (STS) for correlation in-situ surface electronic structure with topography on a sub-nanometer scale. In this paper, we report the STS results of thin film TiO2 and Pt-deposited TiO2 annealed at 450℃. It was found that the TiO2 semiconductor changes from n-type to p-type after Pt deposition.Fig. 1 shows the surface electronic property (Ⅰ-Ⅴ curve) of thin TiO2 film measured in air by STS. A steep descent of the anodic tunneling current at ca.- 1.0 Ⅴ and a rapid ascent of cathodic tunneling current at ca. +2.0V. The zero bias represents the Fermi level (Ef). Ef is situated at the Ecb side indicating that the thin TiO2 film possesses the same band gap as that of bulk TiO2 phase ( Egs =3.0 to 3.2 eV). For the sample of Pt-deposited TiO2 film, Pt/(Pt+Ti+O) atomic ratio≈0.2, which indicates that the surface of TiO2 film is partly covered by Pt particles, and there are two types of Ⅰ-Ⅴ curves to be detected. One of them (Fig.2a)is attributed to the electronic property of TiO2, which has same Egs as that shown in Fig. 1. However, the Ef is transferred to valence side (△≈1eV). This phenomenon hints that TiO2 is doped by an impurity which can introduce h+ into TiO2 lattice.Such a type of defects may be described by Ti1-xPtxO2(h )2x, here Pt+2 as a substitutional site of Ti+4. Fig.2b is the Ⅰ-Ⅴ curve of a Pt particle situated on a TiO2 particle contained Ti1-xPtxO2(h )2x.     

Adsorption-site-dependent electronic structure of catechol on the anatase TiO2(101) surface

The adsorption of catechol (1,2-benzendiol) on the anatase TiO(2)(101) surface was studied with synchrotron-based ultraviolet photoemission spectroscopy (UPS), X-ray photoemission spectroscopy (XPS), and scanning tunneling microscopy (STM). Catechol adsorbs with a unity sticking coefficient and the phenyl ring intact. STM reveals preferred nucleation at step edges and subsurface point defects, followed by 1D growth and the formation of a 2 × 1 superstructure at full coverage. A gap state of ～1 eV above the valence band maximum is observed for dosages in excess of ～0.4 Langmuir, but such a state is absent for lower coverages. The formation of the band gap states thus correlates with the adsorption at regular lattice sites and the onset of self-assembled superstructures.     

Electronic coupling in iron oxide-modified TiO2 leads to a reduced band gap and charge separation for visible light active photocatalysis

In recent experiments Tada et al. have shown that TiO(2) surfaces modified with iron oxide display visible light photocatalytic activity. This paper presents first principles simulations of iron oxide clusters adsorbed at the rutile TiO(2) (110) surface to elucidate the origin of the visible light photocatalytic activity of iron oxide modified TiO(2). Small iron oxide clusters adsorb at rutile (110) surface and their presence shifts the valence band so that the band gap of the composite is narrowed towards the visible, thus confirming the origin of the visible light activity of this composite material. The presence of iron oxide at the TiO(2) surface leads to charge separation, which is the origin of enhanced photocatalytic efficiency, consistent with experimental photoluminesence and photocurrent data. Surface modification of a metal oxide is thus an interesting route in the development of visible light photocatalytic materials.     

Morphology of RuO2-TiO2 coatings and TEM characterization of oxide sols used for their preparation

Characterization of RuO(2) and TiO(2) sols of different aging times, obtained by forced hydrolysis of appropriate chloride salts, was performed by transmission electron microscopy (TEM). The aging time of TiO(2) sols was observed to affect the size of particles as well as the crystallinity of the solid phase of the sols. The surface morphology of RuO(2)-TiO(2) coatings on titanium, obtained by the sol-gel procedure using TiO(2) sols of different aging times and RuO(2) sol of fixed aging time, was investigated by scanning tunneling microscopy (STM) at three different scan sizes. The STM data indicated uniform microdistribution of the coating material (small microroughness) and an increase in nanoroughness with the aging time of the TiO(2) sol. The observed increase in real coating surface area with increasing TiO(2) particle size confirms the earlier cyclic voltammetry results.     

Adsorption and assembly of copper phthalocyanine on cross-linked TiO2(110)-(1 x 2) and TiO2(210)

Copper phthalocyanine (CuPc) on reconstructed rutile TiO(2) was studied with ultrahigh vacuum variable temperature scanning tunneling microscopy. On cross-linked TiO(2)(110)-(1 x 2), the CuPc molecules at low coverages sparsely lay flat at the link sites and tilted in troughs between [001] rows. Increase of the CuPc coverage led to the trapping of the CuPc molecules by the rectangular surface cells fenced by the oxygen columns along the [001] direction and the cross-link rows. Each cell could trap one CuPc molecule at intermediate coverages and two CuPc molecules at higher coverages. On TiO(2)(210), the CuPc molecules tilted in defect-free areas and lay at defect sites with their molecular planes parallel to the substrate surface. Further increase of the CuPc coverage induced the formation of one- and two-dimensional assemblies on TiO(2)(210).     

The importance of bulk Ti3+ defects in the oxygen chemistry on titania surfaces

The role of bulk defects in the oxygen chemistry on reduced rutile TiO(2)(110)-(1 × 1) has been studied by means of temperature-programmed desorption spectroscopy and scanning tunneling microscopy measurements. Following O(2) adsorption at 130 K, the amount of O(2) desorbing at ～410 K initially increased with increasing density of surface oxygen vacancies but decreased after further reduction of the TiO(2)(110) crystal. We explain these results by withdrawal of excess charge (Ti(3+)) from the TiO(2)(110) lattice to oxygen species on the surface and by a reaction of Ti interstitials with O adatoms upon heating. Important consequences for the understanding of the O(2)-TiO(2) interaction are discussed.     

STM study of glycine on TiO2(110) single crystal surfaces

The adsorption of glycine (NH2CH2COOH) was examined by scanning tunneling microscopy (STM) on TiO2(110) surfaces at room temperature. A (2x1) ordered overlayer was observed on the TiO2(110)-(1x1) surface. The adsorption of acetic acid and propanoic acid was also investigated on this surface and their STM images were quite similar to that of glycine. Since acetate and propanoate are formed by dissociative adsorption of these acids on TiO2(110), it is proposed that glycine adsorbs in the same way to form a glycinate. The amino group in the glycinate adlayer structurally analogous to those formed from aliphatic carboxylic acids would be extended away from the surface and potentially free to participate in additional reactions. The underlying structure of the TiO2 surface is important in determining the structure of the glycinate adlayer; no ordering of these adsorbates was observed on the TiO2(110)-(1x2) surface.     

Microfaceting explains complicated structures on rutile TiO2 surfaces

Surface structures on rutile TiO2 (001) have been studied by using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and density functional calculations. Prior investigations have observed many kinds of complicated surface structures; however, detailed atomic structures and the mechanism of the reconstructions are still unknown. We evaluate the energetical stability of the surface structures. The calculational results suggest that a [111] microfaceting model is energetically stable compared with the unreconstructed (1 x 1) model. We propose microfaceting structural models that are in good agreement with atomically resolved STM images. This structural concept can be extended to other rutile TiO2 surfaces in general.     

Ordering of TiO2-based nanostructures on SrTiO3(001) surfaces

A class of nanostructured surface phases on SrTiO3(001) is reported and characterized through atomic-resolution scanning tunneling microscopy and Auger electron spectroscopy. These surface phases are created via argon ion sputtering and UHV annealing and form close-packed domains of highly ordered nanostructures. Depending on the type of nanostructures present, the domain ordering exhibit either (6 x 2), (9 x 2), (12 x 2), (6 x 8), or (7 x 4) surface patterning. The nanostructures are composed of TiO2-derived complexes surrounded by a TiO2 surface termination. Such surface ordering phenomena introduce another level of complexity in the chemistry of perovskite oxide surfaces and provide a basis from which potential photocatalytic and molecular-ordering applications may be developed.     

Preparation and photocatalytic activity of TiO_2-coated granular activated carbon composites by a molecular adsorption-deposition method

TiO2 nanoparticle-coated granular activated carbon (GAC) composite photocatalysts (CPs) were suc-cessfully prepared by a molecular adsorption-deposition (MAD) method. The CPs were detected by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), BET surface area and UV-Vis adsorption spectroscopy, and their photoactivity was evaluated by methyl orange (MO) photodegradation. The results show that small-sized TiO2 nanoparticles were dispersed well, deposited on the surface of GAC, and showed slight blue shift in comparison with pure TiO2. With the increase in TiO2 content, the CPs showed band gaps in lower energy, smaller surface areas and the higher content of Ti3 ions. Compared with pure TiO2 and others CPs samples, CPs-382 sample showed the highest photoactivity due to the optimum TiO2 content and surface area besides the synergic effect of photocatalytic degradation of TiO2 and adsorptive property of GAC. In addition, the CPs could be very easily reclaimed, recycled and reused for methyl orange removal while high photoactivity is pre-served.