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采用一步水热法,以NH4HF2作为形貌控制剂、反应温度为200℃、反应时间为12h,制备锐钛矿型TiO2空心微球,并通过紫外光还原法在TiO2表面沉积单质银.采用SEM、TEM、XRD以及EDS对样品进行表征,以罗丹明B作为模拟污染物表征样品的催化性能.锐钛矿型TiO2空心微球在40 min时降解率达93%,载银二氧化钛复合材料的光催化性能优于纯二氧化钛,当载银量达到2.5%时,光催化活性最佳,在30 min时降解率为98%.采用抑菌圈法表征其杀菌性能,其抑菌圈的直径达16 mm. 相似文献
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以硅酸钠为硅源,硫酸为酸化剂,聚乙二醇为模板剂,利用均相反应器水热法制备了介孔二氧化硅微球.考察硅酸钠、硫酸、聚乙二醇的浓度及聚乙二醇聚合度对产物形貌和材料表面特性的影响,研究了介孔二氧化硅微球的形成机理.运用XRD,FT-IR,XRF,SEM,BET等手段对产品进行表征.从表征结果可以看出,所制备的介孔二氧化硅微球球形度良好,粒径分布比较均匀,纯度高,比表面在92~577 m2/g、孔体积在0.141~1.141 cm3/g范围内可调控.通过TEM对聚乙二醇胶束的研究得到介孔二氧化硅微球的形成机理. 相似文献
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微球负载TiO2催化剂的制备与降解苯酚性能 总被引:1,自引:1,他引:0
以粉煤灰中分离的微珠为载体,采用溶胶.凝胶法制备了负载型TiO2光催化剂,通过XRD、SEM技术对粉煤灰微珠负载TiO2光催化剂的晶型结构和形貌进行了表征;采用悬浮体系以苯酚为降解对象,研究了TiO2 光催化活性.结果表明:负载TiO2催化剂在悬浮体系中具有较高的光催化活性,催化剂负载4次,500℃煅烧2h,降解苯酚的能力最强,在苯酚浓度为102 mg/L,120 min降解率达到60%. 相似文献
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采用水热法在无模板条件下以氧氯化锆和硝酸钡为原料合成了中空锆酸钡微球.系统研究了碱浓度、水热时间对锆酸钡粉体微观结构及形貌的影响.对在不同碱浓度不同水热处理时间下获得产物的XRD、SEM、HRTEM分析结果表明,不同碱浓度和水热时间下均获得了钙钛矿结构的锆酸钡;随碱浓度增大,合成的锆酸钡的微观形貌由实心球体向中空微球转变;中空锆酸钡微球的形成是受碱侵蚀和Ostwald熟化机制共同作用引起的. 相似文献
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采用简单的水热溶剂法,以钼酸钠(Na2MoO4·2H2O)为钼源,硫脲(CS(NH2)2)为硫源,通过调控反应温度、反应时间等合成工艺参数,成功制备了花状微球结构的二硫化钼(MoS2)粉末.采用X射线衍射仪(XRD)、扫描电镜(SEM)等对MoS2粉末的结构和形貌进行了表征.结果表明:当反应温度为220℃,反应时间为24 h,反应环境pH=1时,可制备出花状微球结构的MoS2粉末.通过分析MoS2粉末对罗丹明B的光催化降解率研究其光催化性能,对罗丹明B的降解率达到93.83%,是一种理想的光催化材料. 相似文献
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以硫酸钛的水溶液为原料,加尿素作添加剂(尿素与Ti4+摩尔比1:5),较低温度下用水热法在玻璃基板上制备了TiO2微米球,结果显示生成的TiO2晶体为锐钛矿型.并讨论了形成微米球的机理. 相似文献
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利用纳米级二氧化钛(TiO2)溶胶微粒与聚苯乙烯(PS)胶体颗粒的混合悬浮液,以垂直共沉积的方法制备了核壳型PS/TiO2微球的有序排列。当利用煅烧的方法去除PS胶粒晶体模板后,可以形成空心TiO2微球的三维有序排列。考察了混合悬浮液中两种胶体颗粒的体积比(PS∶TiO2=R)对空心TiO2微球有序排列形成的影响。实验结果表明,合适的R值(6∶1)对于空心微球有序排列的形成至关重要。与此同时,浸渍填充法对照实验的结果表明,煅烧过程中TiO2纳米颗粒晶型转化引起的收缩是造成TiO2空心球产生的主要原因。 相似文献
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This study provided a facile method to prepare nano‐TiO2/polystyrene hybride microspheres in ethanol solution. The formation of titanium dioxide (TiO2) nanoparticles and hybrid microspheres were verified by FTIR, SEM, transmission electron microscopy, thermogravimetric analysis, and X‐ray powder diffraction. Monodispersed colloid TiO2 nanoparticles with small particle sizes were obtained, and the average particle size could be effectively controlled from about 10 nm. The antibacterial activity of the organic microspheres and hybride microspheres was also investigated against Escherichia coli. They were able to efficiently inhibit the growth and the multiplication of E. coli under the UV. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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以TiF4为钛源、九水合硝酸铁为掺杂前体,采用水热法制备铁掺杂的TiO2空心微球。采用SEM、TEM、XRD、BET、XPS等技术对样品的形貌、结构、晶型、比表面积、元素组成等进行表征,以亚甲基蓝(MB)的光催化降解为目标反应,评价其光催化活性。结果表明,160℃下水热反应生成的纳米TiO2空心微球晶型为锐钛矿,少量掺铁并不影响微球的形貌及晶体结构。光催化实验表明,160℃下水热反应12 h生成的TiO2空心微球样品均匀性好、光催化活性最佳;铁掺杂能显著提高TiO2空心微球的催化活性,当铁钛比为1.5:100时,所得样品粒径最小,比表面积最大,光催化活性最高。 相似文献
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以H2Ti3O7纳米线为前驱体,通过简单的离子交换和高温焙烧两步制备了具有不同金属掺杂的yM/TiO2催化剂(M=Fe、Co、Ni,y=0.25%、0.75%、1.25%、1.75%、2.25%,y表示金属M的质量百分比).通过XRD、SEM、TEM、XPS对催化剂进行了表征,考察了yM/TiO2催化剂在以H2O2为氧化剂催化氧化N-甲基吗啉(NMM)合成N-甲基氧化吗啉(NMMO)反应中的催化性能.结果显示,掺杂的金属元素均匀分散在制备的TiO2纳米线基体表面,yM/TiO2催化剂形貌为纳米线/纳米棒.当掺杂的金属Fe含量为1.75%时,催化剂表面缺陷氧含量高达16.86%,催化性能最佳,在反应温度为35℃、反应3 h后NMMO产率达到97.5%,表明金属离子的掺入造成TiO2晶体结构中局部晶格扭曲,导致催化剂表面形成较多的氧空位,提升了催化活性. 相似文献
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Jae-Kyung Oh Jin-Kyu Lee Sung Justin Kim Kyung-Won Park 《Journal of Industrial and Engineering Chemistry》2009,15(2):270-274
The TiO2 nanoparticles with anatase (5.7–12.7 nm), rutile (5.4–8.8 nm), mixed (4.4–8.6 nm) phase were individually prepared using the hydrothermal method. The structure and shape of the particles could be controlled by careful alterations of the hydrothermal conditions. Herein, the TiO2 nanoparticles were successfully synthesized by employing Ti-isopropoxide as the titanium source into hydrochloric acid solution at mild conditions. The crystal structures such as anatase, rutile and mixed phase of TiO2 nanoparticles were determined by means of concentration of hydrochloride. Especially, we observed that the rutile TiO2 crystallites were grown into one-dimensional nanostructures, especially, nanowires, with increasing reaction time. The mechanism of the crystallization of the nanoparticles and the growth habit of TiO2-rutile structure were discussed. 相似文献
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Zhenfeng Zhu Juan Du Junqi Li Yanli Zhang Dianguang Liu 《Ceramics International》2012,38(6):4827-4834
BiVO4 hollow microspheres have been synthesized in the presence of ethylenediaminetetraacetic acid (EDTA) by a microwave hydrothermal method. The as-prepared hollow microspheres were composed of hundreds of nanorods. Increasing the amount of EDTA produced a new nanocage structure. The evolution process of BiVO4 with different microstructures indicated that the amount of EDTA added played a crucial role in determining the shape of the samples. Additionally, it was found that the existence of EDTA was vital to mediate the crystal growth, and the hydrothermal time and temperature were key parameters in determining the BiVO4 morphologies. A possible formation mechanism is proposed. 相似文献
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在低酸度硫酸体系中,以P123 (EO20PO70EO20)为模板剂水热法一步合成硫酸化锆掺杂PHTS固体酸催化剂(SO2-4/Zr-PHTS),利用XRD、TEM、N2吸附脱附以及NH3-TPD、Py-FTIR等手段对其进行表征.结果表明,SO2-4/Zr-PHTS具有有序的六方相介孔结构,具有以L酸为主的弱、中强度的酸性中心;随着硅锆摩尔比的增加,其酸量逐渐减少,比表面积逐渐增加,孔容、孔径无显著变化.SO2-4/Zr-PHTS在催化四氢呋喃聚合中表现出良好的反应性能,推测固体酸的表面酸性和孔结构决定着催化四氢呋喃聚合的反应性能. 相似文献
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Walnut-like In(2)S(3) microspheres were synthesized through an ionic liquid-assisted solvothermal method for the first time. The crystal structure and morphology of the as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectra (DRS) and nitrogen adsorption-desorption measurement. It was found that the additional amount of ionic liquid, solvothermal temperature and time played crucial roles in controlling the structure and morphology of the In(2)S(3) microspheres. A possible formation mechanism of the walnut-like In(2)S(3) microsphere was proposed on the basis of the experimental results. 相似文献