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1.  Synthesis and photocatalytic property of the ZrO2/TiO2 pillared laponite  
   林英光《武汉理工大学学报(材料科学英文版)》,2011年第26卷第5期
   The ZrO2/TiO2 pillared laponite (Ti-Zr-lap) photocatalysts were prepared with intercalation reaction by supercritical fluid drying (SCFD),and characterized by XRD,TEM,SEM and BET surface area analysis,and the photocatalytic properties of Ti-Zr-lap were investigated by degradation of azo dye acid red B (ARB).The results showed that the ZrO2/TiO2 pillared structures in laponite could be formed,with the mass fraction of (Zr4++Ti4+)/laponite (Xm) increasing,the basal spacing and the BET surface area of Ti-Zr-lap significantly increased.The Ti-Zr-lap used as photocatalyst had the advantages of stable and porous layered structure,large surface area with the anatase type TiO2.Compared with the Ti-Zr-lap dried by air drying,the Ti-Zr-lap dried by SCFD showed better photocatalytic property which was very close to that of P25 TiO2.Using the Ti-Zr-lap as photocatalyst with the optimum Xm of 0.16 and the calcination temperature of 500 ℃,under the conditions of the initial concentration of ARB 20 mg/L,photocatalyst concentration of 1.5 g/L and irradiation time 60 min,the decoloring rate of ARB could achieve 98.3%,indicating that the Ti-Zr-lap had excellent photocatalytic property.    

2.  Preparation of titanium dioxide from titania-rich slag by molten NaOH method  
   Yan-fang Han  Ti-changSun  Jie Li  Tao Qi  Li-na Wang  Jing-kui Qu《北京科技大学学报(英文版)》,2012年第3期
   Preparing titanium dioxide from titania-rich slag(TiO2 73wt%) by molten NaOH method has been developed.The effects of tem-perature and reaction time on the titanium conversion were investigated.The results showed that temperature had significant influence on the titanium conversion as well as the structure of the product.About 92% of titanium in the titania-rich slag could be converted after reacting with NaOH at 500℃ for 1 h.Metatitanic acid was formed through the steps of washing treatment,acid dissolution,and hydrolysis.Well-dispersed spherical titanium dioxide particles with an average size of 0.1-0.4 μm can be obtained by calcination of metatitanic acid.In addition,the content of titanium dioxide in the product is up to 98.6wt%,which can be used as pigments after further treatment of coating and crushing.    

3.  Photocatalytic degradation of dimethomorph on nanometer titanium dioxide by silver depositing in aqueous suspension  
   阎建辉 黄可龙 刘素琴 曾恒志《中国有色金属学会会刊》,2005年第15卷第3期
   A series of catalysts of nanometer TiO2 were prepared by silver depositing. The photocatalytic degradation of dimethomorph in an aqueous suspensions by silver depositing with nanometer titanium dioxide as catalyst was investigated by radiation of UV-light and sunlight. A pseudo-first-order kinetic model was used to describe the results. The effects of the dosage of catalyst, oxidant, pH and radiation source on degradation were examined. The experimental results show that the decomposed rate of DMM is 94% when the dosage of catalyst is 1.25 g/L and the concentration of DMM is 100 mg/L under the conditions of solution pH of 7, the air flow of 1.5 L/min and shining for 5 h by UV-light. When it is shined by sun-light under the same condition, the decomposed rate of DMM is 48 %.The mechanism of decomposition was discussed based on the data by analysis of LC-MS.    

4.  Effect of Microstructure on Electrorheological Property for Pure Particle Material  
   Yanli SHANG  Shuzhen MA  Junran LI  Mingxiu LI  Juan WANG and Shaohua ZHANG State Key Laboratory of Rare Earth Materials Chemistry and Applications  College of Chemistry and Molecular Engineering  Peking University  Beijing 100871  China Department of Chemistry  Hebei Normal University  Shijiazhuang 050091  China Department of Chemistry  Baoding Teacher's College  Baoding 071051  China School of Vehicle and Transmission Engineering  Beijing Institute of Technology  Beijing 100081  China《材料科学技术学报》,2006年第4期
   Pure titanium dioxide (TiO2) particle materials were prepared by hydrolyzing titanium tetrachloride (TiCl4). The microstructures of these materials were determined by X-ray diffraction (XRD), accelerated surface area and porosimetry apparatus (BET), and transmission electron microscopy (TEM). The TiO2 materials obtained by calcinations under different temperatures distinctly revealed different microstructures in crystal structure type, surface area, pore size, pore volume and grain size. The relationship between the microstructure of the TiO2 materials and their electrorheological (ER) activity was investigated. Anatase titania particles have better ER performance than rutile titania particles. Amorphous TiO2 materials display higher ER activity than the crystalline titania materials. A large pore volume can be more advantageous in improving the ER effect of a particle material.    

5.  Effect of Microstructure on Electrorheological Property for Pure TiO2 Particle Material  
   Yanli SHANG Shuzhen MA Junran LI Mingxiu LI Juan WANG Shaohua ZHANG《材料科学技术学报》,2006年第22卷第4期
   Pure titanium dioxide (TiO2) particle materials were prepared by hydrolyzing titanium tetrachloride (TiCl4). The microstructures of these materials were determined by X-ray diffraction (XRD), accelerated surface area and porosimetry apparatus (BET), and transmission electron microscopy (TEM). The TiO2 materials obtained by calcinations under different temperatures distinctly revealed different microstructures in crystal structure type, surface area, pore size, pore volume and grain size. The relationship between the microstructure of the TiO2 materials and their electrorheological (ER) activity was investigated. Anatase titania particles have better ER performance than rutile titania particles. Amorphous TiO2 materials display higher ER activity than the crystalline titania materials. A large pore volume can be more advantageous in improving the ER effect of a particle material.    

6.  Montmorillonite supported titanium/antimony catalyst: Preparation,characterization and immobilization  
   陈贵勇  王小群《武汉理工大学学报(材料科学英文版)》,2014年第29卷第3期
   Montmorillonite supported titanium(Ti-MMT) or antimony catalyst(Sb-MMT) has been a hot area of research on preparing polyethylene terephthalate/montmorillonite(PET/MMT) nanocomposites by in situ polymerization. So removal of Ti or Sb from Ti-MMT or Sb-MMT is not expected during in situ polymerization. Studies on immobilization of Ti or Sb on Ti-MMT or Sb-MMT are seldom reported. In this work, a series of montmorillonite supported catalysts of titanium(Ti-MMT) or antimony(Sb-MMT) and cointercalated montmorillonite of titanium and antimony(Ti/Sb-MMT) were prepared by(1) the reaction of sodium bentonite suspension with intercalating solution containing titanium tetrachloride and/or antimony chloride, and(2) drying or calcinating the products at different temperature(100, 150, 240, 350 and 450 ℃). The physicochemical properties of these MMT supported catalysts were studied by X-ray diffraction(XRD), fourier transform infrared spectroscopy(FT-IR), inductively coupled plasma optical emission spectrometer(ICPOES), N 2 adsorption/desorption isotherms, UV-visible diffuse reflectance spectroscopy(UV-vis) and transmission electron microscopy(TEM). The immobile character of Ti or Sb on MMT supported catalysts was evaluated by a two-step method in deionized water or ethylene glycol. Several results were obtained, i e,(a) during the preparation, with an increase in drying or calcinating temperature, the amount of titanium and/or antimony species remained on these MMT supported catalysts decreased,(b) the experiments about immobile character of Ti or/and Sb showed that with an increase in drying or calcinating temperature, the immobilization of Ti and/or Sb species remained on these MMT supported catalysts increased gradually,(c) Ti-MMT calcinated at 450 ℃ had the biggest pore volume, which means Ti-MMT had the best adsorption application prospect.    

7.  Preparation and photocatalytic activity of B,Y co-doped nanosized TiO2 catalyst  被引次数:1
   石中亮  刘富梅  姚淑华《中国稀土学报(英文版)》,2010年第5期
   The catalysts of un-doped, single-doped and co-doped titanium dioxide (TiO2) powders were prepared by sol-gel method with Ti(OC4H9)4 as a raw material. The photocatalytic decomposition of phenol in aqueous solution under UV light was used as a probe reaction to evaluate their photocatalytic activities. The effects of B, Y co-doping on the crystallite sizes, crystal pattern, surface composition, and optical property of the catalyst were investigated by thermogravimetric differential thermal analysis, X-ray d...    

8.  固体超强酸催化剂SO2-4/TiO2-MoO3的制备及其催化合成缩醛(酮)  
   杨水金     梁永光     余协卿     孙聚堂《中国化学工程学报》,2005年第13卷第1期
   SO4^2-/TiO2-MoO3, a novel solid superacid, has been prepared and its catalytic activity at different synthetic conditions was examined with esterification of n-butanoic acid and n-butyl alcohol as probing reaction.The optimum conditions were also found, that is, the mass ratio of MoO3 used in the compound is 25%, the calcination temperature 450℃, and the soaked consistency of H2SO4 is 0.5mol.L^-1. Then it was applied in the catalytic synthesis of six similar important ketals and acetals as catalyst and revealed high catalytic activity. Under the condition that the molar ratio of aldehyde/ketone to glycol was 1:1.5, the mass ratio of the catalyst to the reactants was 0.5% and the reaction time 1.0 h, the yield of ketals and acetals reached up to 63.2%. The catalyst can be easily recovered and reused.    

9.  Sensitizing Mechanism and Adsorption Properties of Dye—Sensitized TiO2 Thin Films  
   胡智学  戴松元  王孔嘉《等离子体科学和技术》,2002年第4卷第5期
   The dye-sensitized TiO2 complex films were prepared by the dye coat onto TiO2 surfaces,and the sensitizing mechanism and adsorption properties of the dye-sensitized TiO2 complex films were inverstigated.The influence of the application conditions of dye adsorbed on TiO2 films on the amount of dye adsorption was discussed.Experimental results show that the concentration,the temperature of dye solutions and the dipping time of TiO2 films in the dye solutions have a significant influence on the amount of dye adsorption.Cell test indicates that the conversion efficiency of light to electricity increases with the amount of dye adsorption.    

10.  Electrocatalytic Activity of Ti/TiO2 Electrodes in H2SO4 Solution  被引次数:1
   王雅琼  童宏扬  许文林《过程工程学报》,2003年第3卷第4期
   Ti/TiO2 electrodes were prepared with the polymeric precursor method (PPM). The structure and morphology of Ti/TiO2 electrodes were examined with XRD and ESEM. The voltammetric charge (q*) of Ti/TiO2 electrodes as cathode in 0.5 mol/L H2SO4 solution was investigated with cyclic voltammetry. It was found that the electrocatalytic activity of the Ti/TiO2 electrodes was affected by the structure and morphology of the Ti/TiO2 electrodes, in other words, was affected by the calcination conditions of preparing the electrodes. The value of q*in was considerably larger than that of q*out, which means that the ‘inner’ active surface area was much larger than the ‘outer’ active surface area, and ‘inner’ active surface played a main role in the electrocatalytic activity of the Ti/TiO2 electrodes.    

11.  Preparation and visible-light photocatalytic property of nanostructu- red Fe-doped TiO2 from titanium containing electric furnace molten slag  
   Yang Li  Yi Yue  Zai-qing Que  Mei Zhang  Min Guo《北京科技大学学报(英文版)》,2013年第10期
   Nanostructured Fe-doped titanium dioxide was synthesized from titanium containing electric furnace molten slag (TCEFMS) by using an alkali fusion, followed by a hydrolyzation-acidolysis-cMcination route. The effects of Mkali/slag mass ratio, calcinating temperature, calcinating time, and water/slag mass ratio on the extraction efficiency and purity of products were systematically studied in this paper. It is indicated that the best extraction efficiency of nanostructured Fe- doped titanium dioxide is 99.35%, when the molten slag is calcinated at 700℃ for 1 h with the mass ratio of alkali/molten slag of 1.5:1. The influence of alkali/slag mass ratio on the photocatalytic activity of final products was evaluated by the photodegradation of methyl blue under visible light irradiation. A maximum photodegradation efficiency of 88.12% over 30 min was achieved under the optimum conditions.    

12.  Photocatalytic degradation of methyl orange by polyoxometalates supported on yttrium-doped TiO_2  
   王亚军  陆科呈  冯长根《中国稀土学报(英文版)》,2011年第29卷第9期
   A series of novel photocatalysts, H3PW12O40-Y-TiO2 nanocomposites with different H3PW12O40 loading levels (10%-40%) were prepared by impregnation method. And the Y-TiO2 support, doped with yttrium, was synthesized via sol-gel technique. The prepared catalysts were characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), nitrogen adsorption-desorption analysis and scanning electron microscopy (SEM). The processes allowed obtaining Keggin structure and crystallized anatase with large BET surface area as well as uniform distribution. The effects of H3PW12O40 loadings, catalyst dose, initial pH and concentration of dye solution on the degradation kinetics of methyl orange under UV light (λ≥365 nm) were discussed. Kinetics studies showed that the photocatalytic degradation of methyl orange fitted the apparent first-order reaction. Methyl orange was totally degraded in 21 min under optimum conditions: 20% loading, 0.03 g dose and pH 1.0. The catalyst was stable and easily to be separated from reaction system for recovery.    

13.  Effects of current density on preparation of grainy electrolytic manganese dioxide  
   郭华军 朱炳权 李新海 张新明 王志兴 彭文杰 刘鲁平《中南工业大学学报(英文版)》,2005年第12卷第6期
   Grainy electrolytic manganese dioxide was prepared by electrodeposition in a 0.9 mol/L MnSO4 and 2.5 mol/L H2SO4 solution. The structure, particle size and appearance of the grainy electrolytic manganese dioxide were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrographs measurements. Current density has important effects on cell voltage, anodic current efficiency and particle size of the grainy electrolytic manganese dioxide, and the optimum current density is 30 A/dm^2. The grainy electrolytic manganese dioxide electrodeposited under the optimum conditions consists of γ-MnO2 with an orthorhombic lattice structure; the grainy electrolytic manganese dioxide has a spherical or sphere-like appearance and a narrow particle size distribution with an average particle diameter of 7. 237μm.    

14.  Influence of Cr~(3+) Concentration on SO_2 Removal over TiO_2 Based Multi-walled Carbon Nanotubes  
   Yang Yanchun  Jia Fengrui  Jian Weiwei  Zhang Shaopeng  Ma Danzhu  Liu Guangxin《中国炼油与石油化工》,2019年第1期
   In this study, titanium dioxide supported by multi-walled carbon nano tubes(MWCNTs/TiO_2) and Cr-doped TiO_2 supported by MWCNTs(MWNTs/Cr-TiO_2) were synthesized by the sol-gel method. The prepared samples were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, the BrunauerEmmett-Teller analysis, and the Raman spectroscopy. The oxidation and efficiency for removal of SO_2 in a simulated flue gas were investigated experimentally in a fixed-bed reactor. The 15% MWCNTs/Cr-Ti02 sample displayed excellent adsorption properties, and a SO_2 removal rate equating to 30.415 1 mg/g from the simulated flue gas containing 2 300 μg/g of SO_2, 8% of 02, and 5% of H20 was achieved under optimal conditions covering a temperature of 333.15 K, and a space velocity of 1 275 h~(-1). The adsorption process was enhanced because Cr doping modified the pore structure and inhibited the grain growth of TiO_2. In addition, the Freundlich and Langmuir models revealed that SO_2 was mainly adsorbed through chemical adsorption on the sample surfaces, and the thermodynamic model analysis indicated that the adsorption was a spontaneous, exothermic, and entropy-reducing process. The adsorption kinetics of SO_2 can be described by the pseudosecond-order kinetic and the Bangham dynamics models. The possible reaction mechanism involved in desulfurization process was also proposed.    

15.  Influence of Light Calcining Hydration of Magnesite on MgO Sintering  
   LI Huan  YU Jingkun  KUANG Shibo School of Materials    Metallurgy  Northeastern University  Shenyang   China《中国耐火材料》,2009年第18卷第3期
   Sintered magnesia clinker(also called sintered MgO) was prepared with Mg(OH)2(prepared by light calcining hydration of magnesite) and magnesite as starting materials,respectively,by the technical process:light calcining(850 ℃ 1 h) → grinding → molding → firing(1 600 ℃ 3 h).The morphology and structure of light calcined MgO powders prepared with magnesite or Mg(OH)2 were analyzed by XRD,SEM and FT-IR.The sinterability and microstructure of sintered magnesia prepared with magnesite or Mg(OH)2 were researched....    

16.  Preparation of erbium ion-doped TiO2 films and the study of their photocatalytic activity under simulated solar light  
   Hongfei Lin  Yujiao Huang  Shaoni Li  Chunhui Luan  Wei Huang  Xiaodong Wang  Xianshe Feng《半导体学报》,2017年第38卷第11期
   A series of erbium ion-doped TiO2 (Er3+-TiO2) films were prepared by a sol-gel dip/spin coating method, and the effect of the dosage of erbium ion (0-2.0 mol%), the films coating layers (1-5 layers), and calcination temperature (400-700℃) on the film structure and photocatalytic activity were investigated in detail. The films were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal analysis (TG-DTG) and UV-Vis diffusive reflectance spectra (DRS). The results showed that the films were composed of anatase, and no other TiO2 phases (rutile and brookite). With the increase of the erbium ion dosage, the crystal size decreased. Erbium ion doping could enhance the thermal stability of TiO2 and inhibit the increase of the crystallite size. Meanwhile doping of erbium ions gave rise to three typical absorption peaks within the range of visible light (400-700 nm), locating at 490, 523, and 654 nm, attributed to the transition of 4f electrons. The higher calcination temperature led to higher crystallinity and bigger crystal grains. The photocatalytic performance of the films was evaluated by degradation of methyl orange solution under simulated solar light. The highest quality film we prepared was with 4 layers, 1.0 mol% dosage of erbium ion, and the calcination temperature of 500℃. With this film, the degradation percentage of 7.8 mg/L methyl orange solution was up to 53.3% under simulated solar light after 6 h photoreaction.    

17.  Effects of Nitrogen Doping on Microstructure and Photocatalytic Activity of Nanocrystalline TiO2 Powders  
   YANG Zhiyuan ZHOU Aiming《武汉理工大学学报(材料科学英文版)》,2007年第22卷第3期
   Nitrogen-doped TiO2 nanocrystalline powders were prepared by hydrolysis of tetrachloride titanium (TiCl4) in a mixed solution of ethanol and ammonium nitrate (NH4NO3) at ambient temperature and a tmosphere followed by calcination at 400 ℃ for 2 h in air. FTIR spectra demonstrate that amine group in original gel is eliminated by calcination,and the TiO2 powder is liable to absorb water onto its surface and into i ts capillary pore. XRD and SEM results show that the average size of nanocrystalline TiO2 particles is no more than 60 nm and with increasing the calcination temperature,the size of particles increases. XPS studies indicate the nitrogen atom enters into the TiO2 lattice and occupies the position of oxygen atom. The nitrogen doping n ot only depresses the grain growth of TiO2 particles,but also reduces the phase transformation temperature of anatase to rutile. The photocatalytic activity of the nitrogen-doped TiO2 powders has been evaluated by e xperiments of photocatalytic degradation aqueous methylene blue.    

18.  Cerium dioxide as a new reactive sorbent for fast degradation of parathion methyl and some other organophosphates  
   Pavel Janos  Pavel Kuran  Martin Kormunda  Vaclav Stengl  Tomas Matys Grygar  Marek Dosek  Martin Stastny  Jakub Ederer  Vera Pilarova  Lubos Vrtoch《中国稀土学报(英文版)》,2014年第4期
   Cerium dioxide was used for the first time as reactive sorbent for the degradation of the organophosphate pesticides parathion methyl,chlorpyrifos,dichlofenthion,fenchlorphos,and prothiofos,as well as of some chemical warfare agents—nerve gases soman and O-ethyl S-[2-(diisopropylamino) ethyl] methylphosphonothioate(VX).CeO2 specimens were prepared by calcination of basic cerous carbonate obtained by precipitation from an aqueous solution.The CeO2 samples containing certain amounts(1 wt.%–5 wt.%) of the neighboring lanthanides(La,Pr,Nd) were prepared in a similar way from pure lanthanide salts.It was shown that ceria accelerated markedly the decomposition of parathion methyl causing the cleavage of the P-O-aryl bond in the pesticide molecule.A similar reaction mechanism was proposed for the degradation of other organophosphate pesticides and nerve agents.The degradation times(reaction half-times) were in an order of minutes in the presence of CeO2,compared to hours or days under common environmental conditions.The reaction in suitable organic solvents allowed conversions of about 90% for parathion methyl loading of 20 mg pesticide/g CeO2 within 2 h with a reactant half-life in the order of 0.1 min.The key parameter governing the degradation efficiency of CeO2 was the temperature during calcination.At optimum calcination temperature(about 773.15 K),the produced ceria retained a sufficiently high surface area,and attained an optimum degree of crystallinity(related to a number of crystal defects,and thus potential reactive sites).The presence of other lanthanides somewhat decreased the reaction rate,but this effect was not detrimental and permitted the possible use of chemically impure ceria as a reactive sorbent.A fast organophosphate degradation was demonstrated not only in non-polar solvents(such as heptane),but also in polar aprotic solvents(acetonitrile,acetone) that are miscible with water.This opens new possibilities for designing more versatile decontamination strategies.The cleavage of phosphate ester bonds is of a great importance not only for the degradation of dangerous chemicals(chemical weapons,pesticides),but also for interactions of ceria(especially the nano-sized one) in biologically relevant systems.    

19.  Cu/Co/Cr Nanocomposites Obtained from Hydrotalcite Precursors as Catalysts for Thermal Decomposition of Ammonium Perchlorate  
   Hongbo Liu  Bingzhi Guo  Qingze Jiao  Zhiyong Xiong《金属学报(英文版)》,2014年第2期
   A series of Cu/Co/Cr nanocomposites with different Cu/Co/Cr molar ratios were obtained by calcination of Cu/Co/Cr hydrotalcites precursors,which were prepared by a co-precipitation reaction.X-ray diffraction,inductively coupled plasma analysis,and transmission electron microscopy were used to characterize the structure,composition,and morphology of Cu/Co/Cr nanocomposites.The results show that Cu/Co/Cr nanocomposites have both CuCr2O4and CoCr2O4spinel phase.The particle size of Cu/Co/Cr nanocomposites is 15–20 nm and the specific surface area is 95–115 m2/g.Cu/Co/Cr nanocomposites were used as new catalysts for improving thermal decomposition of ammonium perchlorate(AP).Their catalytic activities were investigated using differential thermal analysis and thermal gravimetric analyzer coupled with an online mass spectrometer.The results show that the decomposition temperature of AP lowered 132–146 °C by adding 4 wt% Cu/Co/Cr nanocomposites.Catalytic activities of the prepared nanocomposites depend on the calcinations temperature and addition amount of corresponding nanocomposites.The possible catalytic mechanism of Cu/Co/Cr nanocomposites was also studied and discussed.    

20.  Preparation of (Ti, Sn)O_2 Nano-Composite Photocatalyst by Supercritical Fluid Dry Combination Technology  
   Jingchang ZHANG  Qing LI and Weiliang CAO Institute of Modern Catalysis  The Key Laboratory of Science and Technology of Controllable Chemical Reactions  Ministry of Education  Beijing University of Chemical Technology  Beijing 100029  China《材料科学技术学报》,2005年第21卷第2期
   A series of TiO2-SnO2 nano-sized composite photo-catalysts containing Sn (9.3%-30.1%) were prepared from TiCI4 and SnCl4·5H2O by using sol-gel, supercritical fluid dry and solid-phase reaction (SCFD) combination technology. Characterizations with X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) showed that, in addition to anatase type TiO2, a new active phase (Ti, Sn)O2 (with particle size of 2.0-4.3 nm) formed, and there were no SnO2 crystals observed in the range of the doping concentration studied. Photo-catalytic reaction of phenol was used as a model reaction to evaluate the catalytic activities of the obtained catalysts. Compared with pure TiO2 or Ti-Sn catalyst prepared with general sol-gel method, Ti-Sn nano-composite photo-catalyst thus obtained showed significant improvement in catalytic activity. The photo-catalytic degradation rate of phenol could reach as high as 93.5% after 7 h. The preparation conditions of the new phase (T    

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