CuO纳米颗粒修饰的TiO_(2)纳米管的制备及其性能研究

本研究采用水热法制备了CuO纳米颗粒修饰的TiO_(2)纳米管,采用XRD、ICP-MS、SEM、TEM及UV-Vis等手段,分析了TiO_(2)纳米管的基本物理特性,并将其应用于水解制氢反应中。基本物性分析表明,Cu掺杂对TiO_(2)的晶体结构没有明显的影响,CuO纳米颗粒可成功负载于TiO_(2)纳米管表面,其中Cu掺杂量为3wt%的样品,其结晶性最佳,且表面分布的CuO颗粒数量最为适当。在TiO_(2)纳米管表面负载适量的CuO颗粒,可将其吸收波段从紫外光区红移至可见光区,有效提升其光学活性。水解制氢的实验结果表明,经CuO颗粒修饰后,TiO_(2)纳米管的光催化性能得到大幅提升,其中Cu掺杂量为3wt%时,纳米管的H_(2)产率最高,可达47082μmol·g^(-1);Cu掺杂过量时,会因遮蔽效应而降低纳米管的光催化性能,但H_(2)的产率仍可提升约10倍。

纳米TiO_2改性不饱和聚酯树脂(Nano-TiO_2/UPR)的结构与性能

纳米 Ti O2 改性不饱和聚酯树脂 ,其目的是对不饱和聚酯进行同时增韧增强改性。用“反应法”制备的纳米 Ti O2 /UPR,在纳米 Ti O2 与 UPR之间产生的新化学键将纳米 Ti O2 粒子接入 UPR长链上 ,这种新的结构决定了纳米 Ti O2 /UPR的性能。研究结果表明 ,纳米 Ti O2 /UPR的反应活性高于 UPR,纳米 Ti O2 /UPR的冲击韧性和弯曲强度较 UPR分别提高 46%和 5 5 % ,纳米 Ti O2 /UPR的耐热性及介电性与

Ti/nano-TiO_2-Pt复合电极催化甲醇氧化的研究

采用溶胶-凝胶法(sol-gel)制备纳米TiO2(Ti/nano-TiO2)膜电极,再用电沉积法在纳米TiO2膜上修饰Pt微粒,制成Ti/nano-TiO2-Pt复合电极。用循环伏安法研究了纯Pt丝电极和Ti/nano-TiO2-Pt电极对甲醇氧化的电催化活性以及稳定性。结果表明:对甲醇氧化,复合电极比Pt丝电极具有更高的催化活性,且对甲醇氧化中间产物CO的吸附量少,因而不易中毒;复合电极载铂量达到一定值时,电极具有最强的催化活性。

HIPS/nano-TiO_2复合材料的吸光及光老化性能研究

研究了高抗冲聚苯乙烯／纳米TiO2（HIPS／nano—TiO2）复合材料的吸光及光老化性能，以紫外-可见光（UV—Vis）吸收光谱表征吸光性能，以傅里叶红外（FT—IR）及熔体流动速率（FMI）表征老化样品的结构．结果表明，与钛白粉相比，锐钛矿nano—TiO2对紫外光的吸收加强，但对可见光的反射率咯低．复合材料对250-400nm区域的紫外光有较强吸收，且随纳米质量含量的提高而增强．钛白粉也可提高复合材料的紫外吸收性能，且能大幅度提高对可见光的反射能力．锐钛矿nano—TiO2在老化样品中发挥了刚性粒子增韧作用．光老化后复合材料的力学性能明显优于HIPS老化样品，冲击强度可提高30％以上．光老化集中于HIPS的聚1，4-丁二烯（PB）相，老化以断链方式为主．

家电用HIPS/nano-TiO_2多功能复合材料的性能

研究了家电用HIPS/nano TiO2 多功能复合塑料的加工流变性、母料分散性、吸光行为、抗菌、分解内毒素、分解异味气体及自清洁特性。结果表明 ,使用质量分数在0 5 %～ 2 0 %的nano TiO2 的复合材料加工流动性优于HIPS ;经EVA蜡改性的HIPS/nano TiO2 母料可得到良好分散效果 ;HIPS/nano TiO2 制品表现出良好的紫外吸收能力 ,nano TiO2 质量分数在 1 .0 %左右时 ,制品具有较好的抗菌、分解内毒素效果。

Nano-TiO_2/HIPS母料流变性能的研究

采用RosandRheometer流变仪研究了nano -TiO2 /HIPS母料及EVA蜡改性母料的流变性能。结果表明 ,nano TiO2 对母料的表观粘度影响较小 ,在nano TiO2 质量分数低于 2 0 %时 ,表观粘度仅略高于纯HIPS。在低剪切速率下 ,nano TiO2 可加速熔体偏离牛顿流体的速度 ,体系的粘弹性增强 ;而在较高剪切速率下则相反。EVA蜡可在较大范围内调整母料体系的流变性能。在低剪切速率下 ,EVA蜡质量分数超过 5 %就可明显改善体系的流动性 ,且体系流动行为接近牛顿流体 ,粘弹性很弱 ;在高剪切速率下 ,EVA蜡对体系的流动性影响不大 ,流变行为及粘弹行为与纯HIPS相当。原子力显微镜测试表明 ,采用EVA蜡改性的nano TiO2 /HIPS母料 ,可得到表观及分散性良好的制品。

Degradation of dyestuff wastewater using visible light in the presence of a novel nano TiO_2 catalyst doped with upconversion luminescence agent

A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.

The Inhibition Effect of Tert-Butyl Alcohol on the TiO_2 Nano Assays Photoelectrocatalytic Degradation of Different Organics and Its Mechanism

The inhibition effect of tert-butyl alcohol(TBA), identified as the·OH radical inhibitor, on the TiO_2 nano assays(TNA) photoelectrocatalytic oxidation of different organics such as glucose and phthalate was reported. The adsorption performance of these organics on the TNA photoelectrode was investigated by using the instantaneous photocurrent value, and the degradation property was examined by using the exhausted reaction. The results showed that glucose exhibited the poor adsorption and easy degradation performance, phthalate showed the strong adsorption and harddegradation, but TBA showed the weak adsorption and was the most difficult to be degraded. The degradation of both glucose and phthalate could be inhibited evidently by TBA. But the effect on glucose was more obvious. The different inhibition effects of TBA on different organics could be attributed to the differences in the adsorption and the degradation property. For instance, phthalate of the strong adsorption property could avoid from the capture of·OH radicals by TBA in TNA photoelectrocatalytic process.

Preparation and Properties of Nano-TiO_2 Powders

This paper reports the preparation of nano-TiO2 (about 10 nm) powder by the method of precipitation. In detail, some breparation conditions were investigated in order to find out how to control the grain size and reduce the agglomeration of powders. Also, the reflex spectra of nano-scale powders with different grain size were studied. It tvas found that the wave length and width of reflex spectra are connected with the grain size of nano-TiO2 powders

Preparation and Lubricating Properties of A New Antibacterial Emulsion Containing Nano-TiO_2 for Cold Rolling Strips

A new kind of emulsion containing nano TiO_2 was developed through the dispersion experiment. A commercial emulsion and a prepared by our lab emulsion without nano particles were chosen as controls to test the tribological and antibacterial properties of this new emulsion. The load carrying capacity, friction coefficient and average diameter of wear scars were tested by a four-ball machine and the comprehensive antifriction parameter ω was calculated. The wetting angle was also tested using a JC200C1 wetting angle tester. The micro surface and roughness of rolled strips were analyzed to investigate the tribological performance of the recommended new emulsion in strip production. It is shown that the new nano-emulsion possesses a higher load carrying capacity and wetting ability. Therefore the abrasive/plowing wear is reduced more efficiently with the addition of nano particles, and the micro surface is improved. The density of bacteria in the emulsions was tested after the cold rolling experiment. The emulsion breaking ratio and bacteria density were also tested in different time intervals after the cold rolling experiment. The final p H values and bacteria density of different layers of emulsions were measured and the sediment was analyzed by TEM to evaluate the antibacterial behavior of this new emulsion. It is shown that the density of microbial colonies which led to a corruption of emulsions was decreased about 90% and the effective antibacterial period was prolonged.

Preparation of Nano-Sized TiO_2 Particles by Microemulsion Method

Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and particle size were investigated.The prepared TiO_2 was in the form of anatase after annealing.TiO_2 was characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size.

Plastic Deformation of Nano-TiO_2 Ceramics Prepared by Different Methods

The comparative study of the tensile plastic deformation of nano(n)-TiO2 ceramic prepared byphysical gas condensation (P) and chemical hydrolysis precipitation (C) methods was conductedby a gas pressure forming technique at 750~800℃. The results show that n-TiO2 (P) possessesexcellent property of tensile pIastic deformation comparing with n-TiO2(C). The reason for thisis attributed to the surface cleanness and soft agglomeration of n-TiO2 (P) particfe prepared inreIatively cIean vacuum condition.

Structure,room-temperature magnetic and optical properties of Mn-doped TiO_2 nano powders prepared by the sol-gel process

TiO2 nano powders with Mn concentration of 0 at%-12 at% were synthesized by the sol-gel process, and were annealed at 500 ℃ and 800 ℃ in air for 2 hrs. X-ray diffraction （XRD） measurements indicate that the Mn-TiO2 nano powders with Mn concentration of 1 at% and 2 at% annealed at 500 and 800 ℃ are of pure anatase and rutile, respectively. The scanning electron microscope （SEM） observations reveal that the crystal grain size increases with the annealing temperature, and the high resolution transmission electron microscopy （HRTEM） investigations further indicate that the samples are well crystallized, confirming that Mn has doped into the TiO2 crystal lattice effectively. The room temperature ferromagnetism, which could be explained within the scope of the bound magnetic polaron （BMP） theory, is detected in the Mn-TiO2 samples with Mn concentration of 2 at%, and the magnetization of the powders annealed at 500 ℃ is stronger than that of the sample treated at 800 ℃. The UV-VIS diffuse reflectance spectra results demonstrate that the absorption of the TiO2 powders could be enlarged by the enhanced trapped electron absorption caused by Mn doping.

The Physical and Biological Properties of NanoTiO₂Material

The physical and biological properties of TiO2 materials including nano TiO2, micrometer-TiO2 and nano TiO2 tubes have been studied using scanning electron and infrared spectrometer, X-ray diffraction instrument as well as 3-(4,5- dimethylthiazol 2-yl)-2,5 diphenyltetrazolium bromide (MTT) colorimetric method, respectively. These materials are prepared by chemical deposition and anode oxidation methods, respectively. The sizes of nano TiO2 are 80 nm and 1000 nm, respectively, their infrared properties of absorption are different, the characteristic peaks of the former are 1271,1615, 2957 and 3422 cm-1, the latter are 1645 and 2356 cm-1. The nano TiO2 tubes can be formed by anode oxidation method, its diameters are between 50-100 nm, different nano TiO2 tubes contain different components of oxygen and titanium. In MTT experiment we discover the changes of properties of proliferation of the liver and chick embryo fibroblast cells under influences of nanoTiO2 relative to those of the controlled groups, when small nanoTiO2 suspension is added in these cultivated liquids of cell, but the influence of nano TiO2 on the proliferation of the person’s liver cell is still very small, therefore, the toxicities of nano TiO2 containing 80nm and 1000 nm to these cells are still first score.

Prepared of Nd: TiO₂Nano Particles Powder as IR Filter via Sol-Gel

Doped and undoped nanostructured titanium dioxides were prepared via Sol-Gel method under varying conditions to investigate the effects of neodymium ion doping on the titania optical properties in MID IR range. X-ray diffraction analyses show that the amorphous structure of the prepared samples turns to anatas polycrystalline structure after annealing process at 500°C. FTIR spectrums for pure and doped samples after annealing show a single transmission peak at wave number around 1200 cm-1. The transmission rate of the peak depends on Nd3+ concentrations and its value rises from 1.82% (for pure TiO2) to 86.9% (for doped with 12%wt Nd3+). Shifting on the peak occurs with a maximal shift at 7%wt Nd3+ and then becomes stable at higher concentration. FTIR spectra give a good indication in the direction of preparation of optical band-pass filter at a wavelength around 8.34 μm (~1200 cm-1).

Synthesis of Yb³⁺Doped TiO₂Nano Particles Powder as IR Filter via Sol-Gel

Ytterbium doped TiO2 nano-particles were prepared via Sol-Gel Technique under varying conditions to investigate the effects of Ytterbium ion doping on the Titania optical properties in MID IR range. X-ray diffraction analyses show that prepared Yb3+ doped TiO2 samples have polycrystalline structure in Anatas phase. FTIR spectrums for pure and doped samples after annealing process show a single transmission peak at wave number around 1145 cm-1. Transmission rate of this peak depends on Yb3+ concentrations and its value rises from 1.82% (for pure TiO2) to 58.1% (for doped with 1.13 wt% Yb3+). Slightly peak shift occurs at a lower doping rate with no further response to higher concentration rate. FTIR spectra gives a good indication in direction of preparation of optical band-pass filter at a wavelength around 8.733 μm (~1145 cm-1).

Effect of Nano Size TiO₂Particles on Mechanical Properties of AWS E 11018M Type Electrode

Addition of nano size particles of TiO2 in the coating of shielded metal arc welding electrode (E 11018M) partially substituting the conventional micro size TiO2 was studied for possible enhanced electrode characteristics. The results show that the nano size particle of TiO2 improved recovery of elements such as Mn, Ni, Mo, Ti etc. as well as increased all-weld-metal tensile and charpy impact properties at –51℃. Furthermore, the charpy impact properties were found to be very sensitive to variations in Ti content of the weld deposit.

Surface constructions of nano TiO_2 as the environmental and energy materials

TiO_2 has attracted an increasing attention because of its variety of potential applications in environments and energies,such as gas sensing,self-cleaning,solar energy conversion, wettability and photo-catalysis applications.In this presentation,we summarize some progress in surface constructions of nano TiO_2 and its characterizations of physicochemistry and properties. (1)Superhydrophobic nanostructure TiO_2 films Superhydrophobic nanotube,nanopore and sponge-like structure TiO_2 films are fabricated ...

纳米结构TiO_2/SiO_2的逐层自组装

采用逐层自组装方法在二氧化硅球表面交替组装了十二烷基硫酸钠单分子膜和二氧化钛纳米粒子膜 ,该复合多层膜经高温煅烧后得到了核壳型纳米结构二氧化钛 /二氧化硅复合颗粒 .利用XRD ,SEM ,X射线能谱等对复合颗粒进行了表征 .结果表明 :二氧化钛在复合颗粒表面排列紧密、均匀 ,粒径在 5 0nm左右 ,为锐钛矿型结构 .