45^#钢表面TiO2晶膜的制备、结构及性能研究

以Ti(OBu) 4 为前驱体 ,通过溶胶—凝胶法在 4 5 # 钢表面制备TiO2 晶膜 .用FTIR研究了 80℃、4 0 0℃、6 0 0℃下得到的干凝胶的特性 ,用DTA/TG、XRD、AFM等手段研究了涂膜制备时由凝胶向玻璃态的转变以及涂膜的显微结构 ,用动电位极化曲线评估了涂膜样品的电化学腐蚀行为 .结果表明 ,4 0 0℃、6 0 0℃制得的涂膜为锐钛矿型的TiO2 晶膜且有较好的耐腐蚀性能 .

ZnO/TiO2 Nanocomposite Synthesized by Sol Gel from Highly Soluble Single Source Molecular Precursor

Single source molecular precursors （SSPs） provide an opportunity to get control over the microstructure of nanomaterials at atomic level. A SSP was designed and developed for the synthesis of ZnO/TiO2 nanocomposite by sol gel method. In a typical synthe-sis process, a bimetallic molecular compound with chemical formula [Cl2TiZn（dmae）4] （dmae=dimethylaminoethanol） was synthesized and its chemical composition was deter-mined by elemental analysis. The obtained compound has shown excellent solubility in common organic solvents, a prerequisite for its use in sol gel method as SSP. The SSP ob-tained was controllably hydrolyzed by adding equimolar amount of water using ethanol as solvent to get ZnO/TiO2 nanocomposite gel. The resulting gel was precipitated at pH=9 and sintered at 200 ℃ （T200）, 400℃ （T400）, and 600℃ （T600）. The XRD analyses have shown that the as synthesized （non-sintered, T00） powder was amorphous. However, the crystallinity improved upon sintering, and the XRD analyses revealed that the resulting nanomaterials were composed of mixed oxides i.e., ZnO and TiO2. The ZnO was in wurtzite （hexagonal） while the TiO2 was in brookite （orthorhombic） phase. The increase in particlesize was further confirmed from BET analysis and SEM micrographs. The IR spectra ob-tained for the resulting powder have shown the peculiar vibrational bands for Zn-O and Ti-O. Furthermore, the IR spectra revealed that the non-sintered ZnO/TiO2 nanocomposite had significant number of OH group which was removed upon sintering. The photocatalytic activities of the ZnO/TiO2 nanocomposites were tested. All the samples have shown good photocatalytic activities. However, the T400 has shown higher activity than the T00, T200, and T600. The higher photocatalytic activity of T400 than T00, T200, and T600 may be due to improved crystallinity which ensures efficient grain boundary interfaces.

PREPARATION OF POLYSULFONAMIDE/TiO_2 NANOCOMPOSITES BY SOL-GEL

Polysulfonamide(PSA)was synthesized at room temperature,the polymerization based on terephthaloyl chloride and 3,3’-diaminodiphenylsulfone in the common solvent N,N-Dimethyl-acetamide(DMAc).Polysulfonamide/titanium oxide nanocomposites were prepared by sol-gel method.Tetrabutyl titanate(TBT)was added into the polysulfonamide solution,at the same time,some water was mixed to make the TBT hydrolyze.In the process,hydrochloric acid was used to catalyze the reaction.The polysulfonamide chemistry structure was characterized by FT-IR spectrum.Atomic force microscopy(AFM)was employed to observe the microstructure of the composite film.The thermal property was investigated by TGA.The results show that we have succeeded to synthesize the polysulfonamide,TiO2 particles were well distributed in the composite film and average size was about 20 nm on average,the heat-resistance of nanocomposite was batter than the pure polysulfonamide.

Optimization of the preparation process of nano TiO2 with sol-gel method at low temperature

In this paper, preparation process of nano TiO2 with sol-gel method at low temperature was optimized by response surface method. The nano TiO2 was analysised by DRS and XRD. Result show that： 20mL tetrabutyl titanate, 10mL acetic acid, 6mL ethanol dosage, aging time was 29h, aging temperature was 36℃, Nano TiO2 was prepared under the condition. Particle size of nano particles was 37.3nm, Photodegradation rate was 90.2%. It had good photocatalytic ability.

Low temperature doping of anatase nano TiO2

In this paper. Glucose, nitrate, and urea were respectively used as C, B, and N sources doped TiO2 at low temperature sol gel method, The obtained nano TiO2 was characterized by DRS, FIRT, TG-DTG. The photocatalytic properties and the optical response range of the natase nanocrystalline were analyzed and studied with the hybrid orbital theory. The results show that the band gap of the doped TiO2 was narrow, and the photocatalytic ability could be excited by the visible lighL and the doping of non metallic elements broadens the application range of TiO2, so that it could be excited under the visible light and obtained better use value.

Synthesis of NiMoO_4 nanoparticles by sol-gel method and their structural,morphological,optical,magnetic and photocatlytic properties

Nickel molybdate(NiMoO4)nanoparticles(NPs)were synthesized by sol-gel method.Utilizing water as solvent providescrystalline nanostructures.These nanocrystals were structurally characterized by X-ray diffraction,energy dispersive X-ray analysis(EDX),and Fourier transform infrared spectra.Compositional stoichiometry was confirmed by EDX technique.The size and shapewere observed by scanning electron microscopy(SEM)and transmission electron microscope(TEM).It was found that the obtainedNPs were pure and single phase crystalline with monoclinic structure.The optical properties were studied by ultraviolet-visiblediffuse reflectance spectroscopy(UV-Vis-DRS)and photoluminescence(PL)measurements at room temperature.The magneticproperties were studied by vibrating sample magnetometer(VSM)and results showed superparamagnetic behavior of the obtainednanoparticles.Photocatalytic activity of NiMoO4was studied.The photocatalytic activity of NiMoO4was enhanced with the additionof TiO2.The catalysts NiMoO4,TiO2and NiMoO4-TiO2nanocomposites(NC)were tested for photocatalytic degradation(PCD)of4-chlorophenol(4-CP).It was found that PCD efficiency of NiMoO4-TiO2NC was higher than that of pure NiMoO4and TiO2.