共查询到19条相似文献,搜索用时 625 毫秒
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采用聚焦脉冲激光轰击(PLA)浸于流动乙醇中不同金属氧化物掺杂的二氧化钛固体靶,连续制备得到一系列经MoO3、Eu2O3、Fe2O3、WO3等掺杂的新型纳米TiO2乙醇溶胶。UV-Vis、荧光光谱和XRD结果表明:在所研究的掺杂纳米TiO2乙醇溶胶中,MoO3掺杂使纳米TiO2乙醇溶胶荧光增强最大,当MoO3掺杂量(ψ)在0.02%~0.50%时,其掺杂的纳米TiO2乙醇溶胶荧光强度增强,掺杂量为0.05%时荧光强度高达1.3×104(a.u.);此外发现与sol-gel掺杂法相比,预研磨混合掺杂能更明显增强纳米TiO2乙醇溶胶荧光。 相似文献
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利用水热法合成了Fe3+掺杂的三维分级纳米Bi2WO6,借助X射线衍射(XRD)、场发射扫描电镜(FE-SEM)、透射电镜(HRTEM)、能谱(EDS)、紫外可见漫反射(UV-Vis-DRS)等测试手段对所得样品的相组成、形貌和谱学特征进行了表征。选择罗丹明B为模型污染物研究所得样品在可见光下的催化活性。结果表明,Fe3+掺杂Bi2WO6为新颖的分级纳米结构,且Fe3+掺杂能有效提高Bi2WO6的光催化活性,Fe3+掺杂量对Bi2WO6活性的影响显著;实验结果还表明,所得Fe3+掺杂Bi2WO6催化剂的稳定性较好,易于回收。此外,还对Fe3+掺杂Bi2WO6的光催化活性增强机理进行了研究,缺电子的Fe3+作为电子捕获中心有利于促进光生电子-空穴对的分离,从而提高Bi2WO6的光催化活性。 相似文献
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以五水合硝酸铋和二水合钨酸钠为原料,以十六烷基三甲基溴化铵(CTAB)为溴源,制备Br掺杂Bi2WO6,通过调节CTAB的含量,利用水热法制备了Br掺杂量不同的Bi2WO6催化剂。以抗生素环丙沙星、诺氟沙星作为污染物,测试Br掺杂Bi2WO6催化剂的光催化性能。结果表明,2%掺杂量(物质的量分数)的Bi2WO6相比于Bi2WO6的光催化降解性能最好。此外,通过X射线粉末衍射、红外光谱、扫描电镜、荧光光谱、X射线光电子能谱和拉曼光谱等一系列表征,对Br掺杂后催化剂的物相组成、微观形貌、光生电荷分离率和光学性质等进行分析。最后进行了自由基捕获实验并提出了可能的光催化机理。 相似文献
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通过溶胶和超临界干燥方法制得了Fe2O3/Al2O3二元气凝胶,其比表面积和孔隙体积分别为246 m2·g-1和1.89 cm3·g-1,并具有较宽的孔径分布。以Fe2O3/Al2O3二元气凝胶作催化剂,通过甲烷催化裂解成功地合成了高质量的单壁纳米碳管。利用FESEM、TEM和HRTEM、Raman光谱等分析手段研究了反应温度对单壁纳米碳管生长的影响。结果表明在900 ℃时合成单壁纳米碳管的质量较高,并且合成的炭产物为毡状,该炭产物主要为高质量的单壁纳米碳管。 相似文献
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Orel Boris Grošelj N. Krašovec U. Opara Ješe R. Georg A. 《Journal of Sol-Gel Science and Technology》2002,24(1):5-22
We studied the gasochromic effect of amorphous peroxopolytungstic acid (W-PTA), W-PTA (ormosil) and crystalline WO3 films. These latter films were prepared after a heat treatment of W-PTA/ormosil films at 450°C. The ormosil served as a template, providing the monoclinic WO3 films with adequate porosity. The spill-over effect was attained by impregnating the porous WO3 crystalline films with H2PtCl6 followed by a heat treatment at 380°C. The amorphous films became gasochromic with the addition of PdCl2 to the corresponding W-PTA and W-PTA/ormosil sols.Structural features of all the films were studied with the help of infrared (IR) spectroscopy and transmission electron microscopy (TEM). In situ IR spectra of the films, performed in the presence of reducing (H2/Ar) and oxidising (O2/Ar) gases, revealed a reversible transformation of the monoclinic to the tetragonal H
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WO3 phase. At the same time the coloration (reduction) of the amorphous films was accompanied by the formation of coordinated water molecules and increased numbers of W=O bonds. Gasochromic colouring/bleaching changes and the corresponding kinetics were assessed from in situ UV-visible transmission measurements on the films. 相似文献
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Jian Li Qiao-Ling Zhao Guo-Yi Zhang Jian-Zhuang Chen Liang Zhong Lei Li Jin Huang Zhi Ma 《Solid State Sciences》2010,12(8):1393-1398
A monoclinic tungsten trioxide (WO3) nanosphere film was synthesized via a sol–gel approach using an amphiphilic diblock copolymer polystyrene-b-polyacrylic acid (PS-b-PAA) as template in toluene. The morphology, surface area and crystal structure of as-synthesized WO3 were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET (N2) and powder X-ray diffraction (XRD). The XRD pattern of WO3 nanosphere film can be identified as a pure monoclinic WO3 phase. The WO3 precursor nanospheres had diameters ranging from 20 to 150 nm and surface area of 78.8 m2 g?1. The hydrogen gasochromic experiments revealed that such WO3 nanosphere film with high surface area had a rapid response (5 ~ 10 s) to pure hydrogen at room temperature. 相似文献
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B. Orel U. Opara Krašovec U. Lavrenčič Štangar P. Judeinstein 《Journal of Sol-Gel Science and Technology》1998,11(1):87-104
This paper reports on the development of all sol-gel EC devices, having the configuration WO3/ormolyte/SnO2:Mo, WO3/ormolyte/SnO2:Sb and WO3/ormolyte/SnO2:Sb:Mo, where all three internal layers, including the ionically conductive inorganic-organic hybrid (ormolyte), are prepared via the sol-gel route. The electrochemical and optical properties of EC devices are presented and their cycling stability and reversibility of their optical modulation assessed. The transmission modulation of the devices depends on the thickness of the active electrochromic, counter-electrode and ormolyte layer. The electrochemical and optical properties of individual films and the structural properties of the ormolyte are described and correlated with the stability of the all sol-gel EC devices. 相似文献
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以Na_2WO_4·2H_2O和Bi(NO_3)_3·5H_2O为主要原料,采用水热法合成了稀土离子Tm~(3+)掺杂的Bi_2WO_6光催化剂。采用XRD、SEM、TEM、Raman、PL、DRS研究了Tm~(3+)掺杂Bi_2WO_6的物相,微观形貌和可见光催化性能。结果表明,Tm~(3+)掺杂有效提高了Bi_2WO_6的光催化性能,当掺杂量为6%时,样品的光催化性能最好,可见光照射30 min后,对罗丹明B的降解效率达到91.27%,而可见光照射5 h后,对焦糖色素的降解效率达45.25%。与未掺杂Bi_2WO_6相比,分别提高了27.78%和35.22%。 相似文献
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本文综述了制备TiO2薄膜的各种方法,详细介绍了阳极氧化法制备TiO2多孔膜的进展,在非含氟电解液体系中,对纯钛进行阳极氧化处理可制得表面呈无规则生长的多孔膜结构;在含氟电解液体系中,则可自组织形成高度有序的TiO2纳米管阵列,并指出阳极氧化法是可在常温低压下进行、操作工艺简单、薄膜性能稳定、再现性好的一种最具工业化应用潜力的制备方法。 相似文献
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以Na2WO4·2H2O和Bi(NO3)3·5H2O为主要原料,采用水热法合成了稀土离子Tm3+掺杂的Bi2WO6光催化剂。采用XRD、SEM、TEM、Raman、PL、DRS研究了Tm3+掺杂Bi2WO6的物相,微观形貌和可见光催化性能。结果表明,Tm3+掺杂有效提高了Bi2WO6的光催化性能,当掺杂量为6%时,样品的光催化性能最好,可见光照射30 min后,对罗丹明B的降解效率达到91.27%,而可见光照射5 h后,对焦糖色素的降解效率达45.25%。与未掺杂Bi2WO6相比,分别提高了27.78%和35.22%。 相似文献
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Nano oxides (SiO2, CeO2, SnO2) were successfully synthesized by solid-state reactions at ambient temperature. The nanoparticles were characterized by X-ray powder diffraction, TEM, BET, and TGA-DTA. The SiO2 particles were also investigated using IR spectra. Effects of calcination on the nanoparticles were studied in this paper. The solid-state reaction technique is a convenient, inexpensive and an effective preparation method of monodisperse oxide nanoparticles in high yield. The mechanisms of the formation of nano materials by solid-state reactions at ambient temperature were primarily investigated. 相似文献
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以Bi(NO3)3·5H2O和Na2WO4·2H2O为主要原料,采用水热法合成了纯相Bi2WO6,并对其进行非金属离子Br-掺杂改性。采用XRD、SEM、TEM、XPS、Raman、PL和DRS研究了Br-掺杂对Bi2WO6的物相结构、形貌和可见光催化性能的影响。结果表明,Br-掺杂可有效提高Bi2WO6的可见光催化性能,当掺杂量(物质的量百分数)为8%时,溴掺杂Bi2WO6的光催化性能最好,可见光照射40 min后,可降解96.73%的罗丹明-B,与未掺杂Bi2WO6相比,其降解率提高了36.32%。 相似文献