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LIMIN QI JIMING MA HUMIN CHENG ZHENGUO ZHAO 《Journal of Materials Science Letters》1997,16(21):1779-1781
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《Materials science & engineering. C, Materials for biological applications》2003,23(6-8):1033-1038
In present work, nanocrystalline zirconia and titania were synthesized by hydrothermal treatment of zirconyl ZrO(NO3)2 and titanyl TiO(NO3)2 nitrates aqueous solutions and amorphous gels of the corresponding hydroxides. The hydrothermal synthesis was performed in a wide range of temperatures (150–250 °C), concentration of starting solutions (0.25–0.5 M) and duration of the process (from 10 min to up to 24 h). The hydrothermal treatment at high pressure about 2.0–4.0 GPa was also carried out. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and BET. Particle sizes, morphology and properties of the products were investigated. The influence of hydrothermal synthesis conditions on ZrO2 and TiO2 phase compositions were established. 相似文献
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《Journal of Experimental Nanoscience》2013,8(18):1358-1373
This work reports the synthesis of TiO2 nanoparticles via ionic liquid-assisted hydrothermal method at 130?°C for two days. The obtained product was characterised by various techniques. The X-ray diffraction data reveal the anatase phase TiO2 nanoparticles with crystallite size 37 nm. The Fourier transform infrared spectrum shows a band at 400 cm?1 due to Ti–O–Ti stretching vibration, in addition to the presence of ionic liquid. The UV–Vis spectrum of TiO2 nanoparticles shows an absorption band at 314 nm which indicates a blueshift compared with that of bulk TiO2. The transmission electron microscopy images show almost spherical-shaped nanoparticles with an average diameter of 40–80 nm. TiO2 nanoparticles exhibit excellent photocatalytic activity for the degradation of trypan blue, and also help in the reduction of Cr+6 to Cr+3. TiO2 nanoparticles modified glassy carbon electrode exhibits better electrocatalytic oxidation towards dopamine compared with bare glassy carbon electrode. 相似文献
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Tin oxide (SnO) powders were obtained by the microwave-assisted hydrothermal synthesis technique using SnCl2·2H2O as a precursor. By changing the hydrothermal processing time, temperature, the type of mineralizing agent (NaOH, KOH or NH4OH) and its concentration, SnO crystals having different sizes and morphologies could be achieved. The powders were characterized by X-ray diffraction (X-ray), Field Emission Scanning Electron Microscopy (FE-SEM), High Resolution Transmission Electron Microscopy (HR-TEM) and Selected Area Electron Diffraction (SAED). The results showed that plate-like form is the characteristic morphology of growth and the TEM analyses indicate the growth direction as (200). 相似文献
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纳米羟基磷灰石粉体的水热合成 总被引:1,自引:0,他引:1
采用Ca(NO3)2·4H2O和(NH4)3PO4·3H2O作为反应前驱物,通过水热合成颗粒尺寸在100nm以下的短棒状或针状HA晶体.X射线衍射(XRD)、透射电镜(TEM)和红外光谱(FTIR)分析讨论水热温度、反应时间、表面活性剂和烧结与物相组成、晶粒尺寸和晶体形貌的关系.实验结果表明升高反应温度和延长反应时间有利于HA的生成;表面活性剂有助于改善粉体的分散性能;烧结能提高晶体的结晶程度,但粉体易团聚,当温度高于800℃时HA发生分解. 相似文献
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纳米二氧化钛的晶型转变及光催化性能研究 总被引:13,自引:0,他引:13
采用溶胶-凝胶法制得稳定的TiO2透明溶胶.凝胶经焙烧制备了纳米TiO2粉体,利用FT-IR、XRD和原子力显微镜(AFM)技术对其进行了结构和形貌表征,考察了其对水杨酸的光催化活性。研究结果表明,醇胺不同的加入量,对TiO2从锐钛矿转变为金红石型的晶相转变温度(600~800℃)有很大影响.FT-IR谱的423cm^-1处吸收峰为金红石型TiO2的特征Ti-O键振动峰,采用310nm的紫外光波长照射时锐钛矿型TiO2粉体具有较高的光催化活性。 相似文献
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TiO2 nanofiber consisting of 15 +/- 5 nm anatase grains was synthesized by hydrothermal treatment of fibrous hydrogen titanate precursor at 180 degrees C for 20 h. The hydrogen titanate precursor was synthesized by hydrothermal treatment of commercial P25 TiO2 powder in 10 M NaOH at 200 degrees C for 20 h followed by soaking in 0.1 M HNO3 to perform ion exchange between the as-synthesized Na titanate and H. By controlling pH of the solution during hydrothermal treatment of the hydrogen titanate precursor, pure anatase TiO2 nanofiber was obtained. Its band-gap energy determined from the onset of diffused reflectance spectrum was 3.19 eV which is equal to that of anatase TiO2 powder. The TiO2 nanofiber showed higher photodecomposition efficiency than the Cotiox KA-100 TiO2 but lower than the P25 TiO2. Photodegradation is the predominant process for 'Reactive blue 171' removal. 相似文献
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A. S. Shaporev V. K. Ivanov A. E. Baranchikov Yu. D. Tret’yakov 《Inorganic Materials》2007,43(1):35-39
The effect of synthesis temperature on the morphology of fine zinc oxide powders prepared by microwave-assisted hydrothermal processing of Zn(OH)2 suspensions has been studied using x-ray diffraction and low-temperature nitrogen BET measurements. The photocatalytic activity of the powders for Methyl Orange photodegradation has been assessed as a function of synthesis temperature. The results indicate that the specific surface of ZnO powders plays a key role in determining their photocatalytic activity. 相似文献
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《Materials Research Bulletin》2013,48(11):4469-4475
Titanium dioxide (TiO2) nanocrystals with specific exposed crystal facet have attracted considerable interest due to their promising applications in the fields of energy and environment. In this paper, we report on a simple solvothermal approach for the synthesis of anatase TiO2 octahedra with high yield, using titanium(IV) sulfate and hydrazine hydrate as the starting materials. The formation mechanism of anatase TiO2 octahedra is suggested. The samples were characterized with XRD, Raman, SEM, TEM, FTIR, XPS, and UV/vis techniques, and further tested as a candidate in photocatalysis to decompose methyl orange in aqueous solution at room temperature. The results show that SO42− ions not only benefit the formation of octahedral nanocrystals, but also inhibit nitrogen doping into TiO2 matrix. More importantly, it is found that the octahedral TiO2 nanocrystals show enhanced photocatalytic activity compared to TiO2 P25 and anatase TiO2 counterparts. 相似文献
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Zhao Yuan Zhang Mengqi Wang Wei Song Wenli Jiang Kanrui Zhang Xiaojuan 《Journal of Materials Science: Materials in Electronics》2021,32(18):22910-22920
Journal of Materials Science: Materials in Electronics - Ti3+/N-co-doped TiO2 was successfully synthesized in situ by one-step hydrothermal method using tetrabutyl titanate (TBOT) as the titanium... 相似文献
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《Materials Letters》2007,61(23-24):4651-4654
Uniform and high-aspect-ratio ZnS nanowires with length up to several micrometers and diameter of 30–50 nm are synthesized by a facile and low-cost microemulsion-mediated solvothermal method. Moreover, ZnS nanorods and bamboo-leaf-like ZnS nanostructures were also obtained by modulating the reaction parameters. Especially, hollow bamboo-leaf-like ZnS nanostructures formed by radiating those bamboo leaves with electron beam. A reasonable mechanism to the formation of the as-prepared one-dimension zinc blend ZnS nanocrystals is also discussed. 相似文献
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Titanium oxide with different ratios of anatase to rutile has been prepared by the microemulsion-mediated solvothermal method. The resulting samples were investigated by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, UV-vis diffuse reflectance spectra, transmission electron microscopy and Brunauer-Emmett-Teller analysis. The contents of anatase and rutile in the TiO2 particles have been successfully controlled by simply adjusting the amount of urea in the aqueous phase of the microemulsion. Both the degradation of Rhodamine B in aqueous solutions and mineralization of TOC revealed that the catalyst containing 47.6% anatase have presented the highest photocatalytic activity. A proposed mechanism is discussed to interpret the evolution of the phases based on the effect of different amount of urea. 相似文献
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Macroporous TiO2 microspheres have been synthesized on a large scale by a facile hydrothermal process using titanium tetrachloride (TiCl4) as the titanium source, ammonium fluoride (NH4F) and hydrogen peroxide (H2O2) as the etchant. X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM) studies show that the anatase TiO2 microspheres are well-crystalline with an average diameter of 5.43 μm. N2 adsorption–desorption and mercury intrusion porosimetry analysis reveal that the as-prepared TiO2 microspheres are composed of numerous pore networks with an average pore diameter of 274 nm and porosity of 39.8%. In addition, the formation mechanisms of macroporous TiO2 microspheres were also investigated. 相似文献
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Zan Li Yang Li Wei Qin Xiaohong Wu 《Journal of Materials Science: Materials in Electronics》2016,27(7):6673-6680
AZO powders were sensitized through chemisorption method by octa-iso-pentyloxy phthalocyanine lead and characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results showed that after sensitization process AZO photo physical properties improved greatly in visible regions. Photocatalytic degradation of methylene blue was studied under visible irradiation in aqueous solution and the pseudo first order model was used to obtain kinetic information of the photocatalytic degradation. The results indicated that photocatalytic activities of PbPc(iso-PeO)8-AZO were better than of AZO powders. 相似文献