詳細検索結果
以下の条件での結果を表示する:
全文: "TTIP"
351件中 1-20の結果を表示しています
  • Yasunobu Akiyama, Katsuya Shitanaka, Hiroshi Murakami
    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
    2008年 41 巻 8 号 779-784
    発行日: 2008/08/20
    公開日: 2008/08/20
    ジャーナル 認証あり
    Titanium oxide (TiO2) thin films were grown on Si(100) substrates using the chemical vapor deposition (CVD) of titanium tetra isopropoxide (TTIP; Ti(OCH(CH3)2)4). The distribution of the growth rate in the reactor and the step coverage of films grown in the range 593–1173 K could was using our “simple reaction model.” The TTIP changed into TiO2 directly via a surface reaction. The surface reaction rate constant was determined by comparing the step coverage of grown and simulated films. The activation energy of the surface reaction was 212 kJ/mol (T < 710 K).
  • Kentaro Ohshima, Yoshifumi Torimoto, Keiichi Tsuto, Kikuo Okuyama, Ryuichi Ushio, Yasuo Kousaka
    KONA Powder and Particle Journal
    1991年 9 巻 59-71
    発行日: 1991年
    公開日: 2014/06/30
    ジャーナル フリー
    The formation of TiO2 thin film and fine particles by the thermal decomposition of titanium tetraisopropoxide (TTIP)vapor was carried out experimentally using a laminar-flow aerosol reactor (LFAR). TTIP vapor and He gas mixture was introduced into a heated pipe in a laminar flow, and the thin films formed and the particles deposited on the pipe wall were observed using an electron microscope under various supplied concentrations of TTIP vapor, reactor temperatures and operating pressure inside the reactor It has been found that the generation of fine particles is enhanced at higher concentration of TTIP vapor, higher reaction temperature and higher pressure, but the formation of thin films is more enhanced lower pressure. The observed trends agreed qualitatively with the simulation results obtained by numerically solving the aerosol dynamic equation where the particle formation was evaluated by a simplified reaction and coagulation model.

    This report was originally printed in KAGAKU KOGAKU RONBUNSHU, 16(3), 535-542 (1990) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Chemical Engineers, Japan.
  • Shinsuke Nagamine, Yoshitaka Tanaka, Masahiro Ohshima
    Chemistry Letters
    2009年 38 巻 3 号 258-259
    発行日: 2009/03/05
    公開日: 2009/02/14
    ジャーナル 認証あり
    Hollow TiO2 fibers were fabricated by electrospinning an aqueous solution of poly(ethylene oxide) (PEO) and introducing the thread-like droplets directly into a titanium tetraisopropoxide (TTIP)/hexane solution, inducing the rapid hydrolysis and condensation of TTIP at the interface between the PEO solution and TTIP solution. Various hollow structures including submicron hollow fibers, thick fibers with a diameter of tens of micrometers, and spherical micron particles could be systematically synthesized by varying the molecular weight and concentration of PEO solution.
  • Ingmar Gerlach, Motoaki Kawase, Kouichi Miura
    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
    2008年 41 巻 6 号 497-506
    発行日: 2008/06/20
    公開日: 2008/06/20
    ジャーナル 認証あり
    By utilizing the pores of carbonaceous materials as a kind of nanoreactor, nanosized titania (TiO2) was prepared. The carbon materials acted as a support matrix for obtained titania nanostructures, which were immobilized on the internal surface. The precursor titanium tetraisopropoxide (TTIP) was first adsorbed in the pores of the carrier material. Titania was subsequently formed within the carrier pores by flash pyrolysis. Space confinement of the pores of the carrier was successfully applied to obtain only nanosized titania formed exclusively at the desired place inside the pores. On the other hand, transport resistance in the small pores and rapid heating helped to maximize titania yields because of quickly reaching a temperature regime where the reaction rate of the precursor exceeded its diffusive flux out of the carrier pores. With this method, titania loadings as high as 14 wt% were achieved. Obtained titania existed as monodisperse nanoparticles of 5 to 8 nm in diameter. The nanoparticles were single-crystalline of both anatase and rutile phases. Process parameters were investigated to clarify the optimum operation mode of the nanoreactor for maximum product yields. The titania yield was found to increase exponentially with rising reaction temperature. Rapid heating allowed for improving the titania yield significantly and was crucial to obtain nanoparticles of a good quality, i.e., narrow size distribution and good dispersion. The pore structure of the carrier material had a notable effect on the titania yield, i.e., the yield at very high temperatures in an ordered pore system were higher than in a random pore system. By variation of the precursor loading and changing the reactant, mass transport mechanisms in the pores could be clarified.
  • 早川 雅浩, Shankar Parajulee, 池澤 俊治郎
    電気学会論文誌A(基礎・材料・共通部門誌)
    2010年 130 巻 8 号 748-752
    発行日: 2010/08/01
    公開日: 2010/08/01
    ジャーナル 認証あり
    TiO2 deposition-methods are versatile and are expected to be more simple and easy, however, in recent years the industrial photocatalytic products have been developed enormously. In this work, photocatalytic TiO2 micro-particles are deposited using the atmospheric pressure plasma jet device. Here, deposition-method is carried out in two steps, at first, the hydrolysis reaction time has been able to control which will resolve the TTIP coagulating trouble during the transportation, by acidifying the solution with AA (Acetic acid) and DEA (Diethanolamine). An experiment was performed to measure the hydrolysis reaction time of TTIP (Titanium tetraisopropoxide) solution by He-Ne laser. Secondly, the deposition of TiO2 micro-particles was carried out using the atmospheric pressure plasma jet with the controlled TTIP solution in reaction time. Based on SEM and water contact angle measurement, it is found that the smaller the mixing ratios of TTIP and DEA the smaller the TiO2 particle size. Also, the smaller the TiO2 particles the smaller the contact angle under the UV irradiation which suffices the photocatalytic behavior.
  • 笹本 忠, 榎本 すみ江, 下田 善也, 佐伯 雄造
    Journal of the Ceramic Society of Japan (日本セラミックス協会学術論文誌)
    1993年 101 巻 1170 号 230-232
    発行日: 1993/02/01
    公開日: 2010/08/06
    ジャーナル フリー
    The relationship between the hydrolysis conditions of titanium tetraisopropoxide (TTIP) and the thermal transformation of the hydrolysis products was investigated as a part of study on the properties of TiO2 formed by the hydrolysis of titanium alkoxide. The amorphous products formed under the HNO3 and HCl acidic conditions transformed to anatase at about 200°C. This temperature was about 100°C higher than that of the amorphous products formed with neutral water, and was not correlated with the H2O/TTIP molar ratio. On the other hand, the anatase-rutile transformation was significantly accelerated under the acidic condition. In particular, the single-phase rutile particles which were needle-shaped and about 0.1μm in length were formed at room temperature when the concentrations of acids were more than 6wt% for HNO3 and more than 4wt% for HCl at the molar ratio of H2O/TTIP=20. In the case of the hydrolysis product formed under H2SO4 acidic condition, on the contrary, the temperatures of the amorphous-anatase and anatase-rutile transformations were higher than those of hydrolysis products with neutral water, and its values were 300 and 700°C, respectively.
  • Yoshiki OKADA, Atsushi MIZUTORI, Daiki YAMAOKA
    エアロゾル研究
    2017年 32 巻 1 号 52-57
    発行日: 2017/03/20
    公開日: 2017/04/03
    ジャーナル フリー

    We studied the formation of non-aggregated Li4Ti5O12 particles by reaction between lithium nitrate and titanium tetraisopropoxide in a methane/oxygen coflow diffusion-flame reactor. We obtained the powder consisting of phase-pure Li4Ti5O12 particles after calcination at 1,073 K. The particles produced in the flame reaction from the spray solution contained an excess amount of lithium corresponding to 25% of the stoichiometric amount. A change in the proportion of virtually non-aggregated particles in TEM images was observed using a rapid cooling of the entire flame aerosol by blowing with cold quenching gas of Ar followed by supercooling in a Laval nozzle placed above the flame. The proportion of non-aggregates was 28% for the particles produced without any cooling steps. When the flame aerosol was supercooled in the Laval nozzle after blowing with 203 K Ar quenching gas, the proportion of non-aggregates was as large as 88%. Thus, rapid cooling in the region of the flame tip is quite effective for preventing particle aggregation.

  • FUKUHARA Yoshiaki, YAMAKAWA Toko, SAKAI Yuka, YAMASAKI Akihiro, SATOKAWA Shigeo, KOJIMA Toshinori
    Journal of Ecotechnology Research
    2010年 15 巻 3-4 号 85-89
    発行日: 2010年
    公開日: 2015/03/11
    ジャーナル フリー
    The authors have so far demonstrated that production of fine TiO2 powder is possible by gas phase hydrolysis of titanium tetraisopropoxide (TTIP). In this paper, the effects are discussed of the shape of reactor and operational condition, such as mixing condition on the produced particle properties especially particle diameter of produced TiO2 fines.
    Our originally designed reactor was used, in which the steam vapor was fed from the bottom of the reactor then transported through an internal thin tube in the heated part of the reactor, and then mixed with TTIP fed from the top of the reactor without heating. The TiO2 fines were produced by 1.00 ml/min of TTIP gas flow (RC I) at 200, 300, 400 and 500°C of the reactor temperature with 10.0 ml/min (at 25°C) of TTIP gas flow (RC II).
    The particle diameter of TiO2 produced by gas phase synthesis was the smallest at 200°C, while the produced TiO2 showed increased crystallinity and photochemical activity with increased reaction temperature. The photocatalytic activity of TiO2 fines produced at 500°C was around 1/10, while that of the calcinated TiO2 fines produced at 200°C under RC II was 1/4 compared with that of JRC-TIO-4, respectively. The results of the photocatalytic activity tests suggested the activity is expected to be increased not only with increased crystallinities but also with decreased particle size.
  • 岡西 茂実, 島川 一, 川田 裏
    化学工学論文集
    1992年 18 巻 3 号 303-307
    発行日: 1992/05/10
    公開日: 2009/11/12
    ジャーナル フリー
    気相加水分解法を用いて, チタンテトライソプロポキシド (TTIP) を加水分解しアモルファスのチタニア超微粒子を生成させ, 引き続き, このチタニア上でアルキルアルコキシラン (AAS) を加水分解させてコーティングし, 表面を安定化させ凝集を防止した.得られた疎水性のチタニア超微粒子の分散性を有機溶媒中での分散粒子径測定と分光透過率により評価したところ, 親水性のエタノール中での分散においては, 加水分解時の水の過剰率を上げることが有効であり, さらに疎水性のトルエン中ではアルコキシ基数の多いAASを用いかつその供給量も多くした方が良いことがわかった.粒子表面の改質状態を29Si-NMRにより評価したところ表面疎水化の程度が分散粒径と相関があり, 加水分解時の水の過剰率を変えることにより表面疎水化の程度および分散性を制御できることがわかった.またこのチタニア超微粒子は有機溶媒に分散させると優れた透明性と紫外線遮蔽性を示した.
  • 福田 徹, 石田 真一, 中釜 達朗, 小池 茂行, 内山 一美
    分析化学
    2005年 54 巻 10 号 969-973
    発行日: 2005年
    公開日: 2005/12/22
    ジャーナル フリー
    It was found that the UV-absorbance of sugar alcohols was enhanced by a reaction with titanium alkoxide {titanium tetraisopropoxide (TTIP)}. 29- and 146-fold increases of the absorbance of sorbitol and xylitol at 250 nm by reactions with TTIP were found, respectively. Good linear relationships (r≥0.9794, n = 5) between the absorbance at 250 nm and the concentration of these sugar alcohols were obtained. When a 4.9 mM sorbitol aqueous solution was used as the sample, the repeatability, including the sample-preparation step, became 6.0% (n = 3) as the relative standard deviation.
  • 金井 貴詩, 小宮山 宏, 井上 博愛
    化学工学論文集
    1985年 11 巻 3 号 317-323
    発行日: 1985/05/10
    公開日: 2009/11/12
    ジャーナル フリー
    チタンテトライソプロポキシド (TTIP) を出発物質として, TiO2微粒子の気相合成を行った.反応管内壁に析出したTiO2の触媒作用によって, 510Kという低温でも合成が可能であった.反応温度, TTIP濃度などの反応条件によって, 生成粒子は, 非晶質, 結晶質 (アナターゼ), 多孔質, 無孔質と特性が変化した.形状は球型で, 平均粒径は反応条件によって0.1~0.5μm程度であった.内壁に析出したTiO2を触媒とする反応の速度は, tangmuir-Hinshelwood型の速度式で良く表現することができる.粒子生成の機構は, 従来想定されてきたような均相核発生・成長機構ではなく, 器壁TiO2上での開始反応, 均相核発生・成長, 凝集による粒子生成という機構であると考えられる.最大300m2/gにも達する球型多孔質体の生成には, 凝集機構が重要な役割を果たしているものと考えられる.
  • Noritsugu Hashimoto, Tadanori Hashimoto, Hiroyuki Nasu, Yoshitsugu Yamamoto, Seiji Niijima
    e-Journal of Surface Science and Nanotechnology
    2006年 4 巻 566-569
    発行日: 2006年
    公開日: 2006/07/22
    ジャーナル フリー
    Ag and TiO2 particles prepared by the evaporation-condensation method and spray pyrolysis, respectively, were mixed in N2 gas flow, and then deposited on the SiO2 glass substrate to form a film. Optical properties of the film thus obtained were evaluated using UV-Visible spectrophotometer and Z-scan technique. As a result, the absorption peak wavelength of Ag particles due to localized surface plasmon resonance (LSPR) was shifted toward longer wavelength side with increasing the concentration of Ti(OC3H7)4 used as a starting material of TiO2 particles. This indicates that LSPR peak of Ag particles is strongly influenced by TiO2 particles. Therefore, this method is useful to develop tunable LSPR devices such as optical switches and sensors. Meanwhile, nonlinear refractive index determined by Z-scan technique was negative. [DOI: 10.1380/ejssnt.2006.566]
  • 岡西 茂実
    粉体工学会誌
    1994年 31 巻 10 号 734-737
    発行日: 1994/10/10
    公開日: 2010/04/30
    ジャーナル フリー
  • 越智 光一, 若尾 和美
    高分子学会予稿集
    2002年 51m 巻
    発行日: 2002/09/18
    公開日: 2004/01/08
    会議録・要旨集 フリー
    Organic/inorganic hybrids containing 4 to 16wt% of titania were prepared from a diglycidyl ether of hydrogenated bisphenol-A(HDGEBA) and a titanium-tetra-iso-propoxide(TTIP) by utilizing a sol/gel process. In the HDGEBA/TTIP hybrids, the storage modulus in the rubbery region kept at a high value even in the high temperature. Observation using transmission electron microscopy (TEM) revealed that the titania network was uniformity dispersed in the hybrids. When the UV light was irradiated to the epoxy/titania hybrids, contact angle was decreasing suddenly, and the hybrid materials conversed the highly hydrophilic surface of titania. As a result, in the hybrids the uniformity dispersing titania network appeared super hydrophilic property. Moreover, anatase phase that has a high photocatalytic activity was dispersed by heat treatment in epoxy resin.
  • 越智 光一, 若尾 和美
    高分子学会予稿集
    2002年 51 巻
    発行日: 2002/05/10
    公開日: 2004/01/08
    会議録・要旨集 フリー
    Organic/inorganic hybrids containing 4wt%- to 16wt% of titania were prepared from a diglycidyl ether of hydrogenated bisphenol-A (HDGEBA) and a titanium-tetra-iso-propoxide (TTIP) by utilizing a sol/gel process. In the HDGEBA/TTIP hybrids, the storage modulus in the rubbery region kept at a high value even in the high temperature. Observation using transmission electron microscopy (TEM) revealed that the titania network was uniformity dispersed in the hybrids. When the UV light was irradiated to the epoxy/titania hybrids, contact angle was decreasing suddenly, and the hybrid materials conversed the highly hydrophilic surface of titania. As a result, in the hybrids the uniformity dispersing titania network appeared super hydrophilic property.
  • Hiroshi Komiyama, Takashi Kanai, Hakuai Inoue
    Chemistry Letters
    1984年 13 巻 8 号 1283-1286
    発行日: 1984/08/05
    公開日: 2006/03/27
    ジャーナル フリー
    Ultrafine TiO2 particles were prepared by chemical vapor deposition of titanium tetraisopropoxide. The particle formation reaction, being catalyzed by the TiO2 deposit on the reactor wall, took place even at as low a temperature as 250°C, according to the stoichiometric relation of Ti(C3H7O) →TiO2 + 4C3H6 + 2H2O. The TiO2 particles were amorphous and porous, the specific surface area of which reached 300 m2/g.
  • Zhixia LI, Masakazu KAWASHITA, Masaaki DOI
    Journal of the Ceramic Society of Japan
    2010年 118 巻 1378 号 467-473
    発行日: 2010/06/01
    公開日: 2010/06/01
    ジャーナル フリー
    We tried to prepare magnetic TiO2 microspheres as thermoseeds for hyperthermia of cancer by a sol–gel process from titanium tetraisopropoxide (TTIP) in a water-in-oil emulsion. The microspheres were prepared by the addition of diethanolamine (DEA) as stabilizer, methanol (CH3OH) as dispersant and colloidal γ-Fe2O3 nanoparticles as origin of magnetization. The γ-Fe2O3 nanoparticles were prepared by an oxidation–precipitation method in FeCl2–NaNO3–NaOH system. The diameter of microsphere was controlled by optimizing preparation conditions, i.e., molecular ratio of reactants and stirring speed. Mono-dispersed magnetic TiO2 microspheres 10–30 µm in diameter were sucessfully obtained by adding a certain amount of water phase with the molar ratio of TTIP/DEA/CH3OH/H2O = 1:1.7:7:22 into kerosene with surfactant (sorbitan monooleate/sorbitan monostearate = 3:1 in weight ratio) 16 wt % of the total amount of oil phase. They contained up to 26.7 wt % γ-Fe2O3 and their saturation magnetization and coercive force were 20.4 Am2/kg and 10 kA/m, respectively.
  • Yukihiro Shimogaki, Hiroshi Komiyama
    Chemistry Letters
    1986年 15 巻 3 号 267-268
    発行日: 1986/03/05
    公開日: 2006/03/27
    ジャーナル フリー
    TiO2 films of 50–100 μm in thickness were formed on a cooled substrate from a stream containing titanium–tetraisopropoxide (Ti(OC3H7)4, TTIP) at 623 K and atmospheric pressure. The films were amorphous and microporous with a specific surface area of 30–50 m2/g. The growth rate of these films, around 30 nm/s, was much higher than conventional deposition techniques.
  • 吉木 宏之, 乙坂 佳輝
    Journal of the Vacuum Society of Japan
    2014年 57 巻 4 号 163-166
    発行日: 2014年
    公開日: 2014/04/30
    ジャーナル フリー
      TiO2 has a photocatalytic function when irradiated with ultraviolet (UV) light. One of photochemical reaction on a TiO2 surface is the photo-induced redox reactions of adsorbed substances, and the other is the photo-induced high hydrophilicity. It is expected, therefore, that a UV transparent glass tube having a TiO2 coated inner wall shows the self-cleaning and hydrophilic properties. TiO2 coating on an inner wall of a narrow (φ2.5 mm) quartz glass tube by an atmospheric-pressure RF (13.56 MHz, 12 W) plasma using titanium tetraisopropoxide (TTIP) as a precursor and a carrier gas He is studied. RF driven parallel-plate electrodes are closely attached on the outer surface of a glass tube to generate He glow plasma inside the tube. It revealed that O2 addition of 2% or more to the TTIP/He gas is key to prepare a pure TiO2, otherwise TiC is mixed among the deposited TiO2 films. The tube inner wall was covered with TiO2 films of 500-900 nm in a thickness after a TTIP/O2(2%)/He plasma treatment for 20 min. TiO2 microparticles with 1-4 μm in a diameter also deposited on an inner wall under the electrodes and the number of microparticles increased with increasing a gas flow rate. It seems that these microparticles are charged negatively and, therefore, are attracted toward the electrodes.
  • Chan Soo Kim, Kikuo Okuyama, Koichi Nakaso, Manabu Shimada
    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
    2004年 37 巻 11 号 1379-1389
    発行日: 2004年
    公開日: 2004/11/20
    ジャーナル 認証あり
    To understand the mechanism by which titania (TiO2) nanoparticles are generated by a CVD method, the primary nucleation mode size distributions of TiO2 nanoparticles prepared from two different chemical precursors (TTIP and TiCl4) were directly measured using a DMA/PSM/CNC system. This represents the first report of such direct measurement in the nucleation mode. These results are particularly important for experimental investigation of particle nucleation and growth, something which has never been achieved before. In the nucleation mode, titania nanoparticles with a diameter of about 2 nm were produced by nucleation. At low reactor temperatures, nucleation and surface reaction were major contributors to particle generation. At a high reaction temperature, coagulation and sintering became more important. The morphology and crystallinity of the particles were investigated by TEM and XRD as a function of temperature and precursor concentration. The properties of the titania nanoparticles, such as particle size distribution, the morphology and crystallinity, changed as a function of reaction temperature and chemical reaction rate.
feedback
Top