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排序方式: 共有802条查询结果,搜索用时 15 毫秒
91.
Rodrigo T. Bento Olandir V. Correa Marina F. Pillis 《Journal of the European Ceramic Society》2019,39(12):3498-3504
Titanium dioxide ceramic coatings have been used as catalysts in green technologies for water treatment. However, without the presence of a dopant, its photocatalytic activity is limited to the ultraviolet radiation region. The photocatalytic activity and the structural characteristics of undoped and sulfur-doped TiO2 films grown at 400 °C by metallorganic chemical vapor deposition (MOCVD) were studied. The photocatalytic behavior of the films was evaluated by methyl orange dye degradation under visible light. The results suggested the substitution of Ti4+ cations by S6+ ions into TiO2 structure of the doped samples. SO42? groups were observed on the surface. S-TiO2 film exhibited good photocatalytic activity under visible light irradiation, and the luminous intensity strongly influences the photocatalytic behavior of the S-TiO2 films. The results supported the idea that the sulfur-doped TiO2 films grown by MOCVD may be promising catalysts for water treatment under sunlight or visible light bulbs. 相似文献
92.
Shensong Wang Zheng Wu Jie Chen Jiangping Ma Jingshi Ying Shouchen Cui Shigang Yu Yongming Hu Jinhe Zhao Yanmin Jia 《Ceramics International》2019,45(9):11703-11708
In this work, the hydrothermally-synthesized sodium niobate nanowires were used to decompose Rhodamine B dye solution through the piezo-catalytic effect. With the sodium niobate catalyst, a high piezo-catalytic degradation ratio of ~80% was achieved under the excitation of vibration for the Rhodamine B dye solution (~5?mg/l). These active species in the catalytic process, hydroxyl radicals and superoxide radicals with the strong oxidation ability, were also observed, which confirmed the key role of piezoelectric effect for piezo-catalysis. The piezo-catalysis of sodium niobate nanowires provides a high-efficiency and reusable tool in application in depredating the dye wastewater. 相似文献
93.
Monika Bosacka Anna Blonska-Tabero Elzbieta Filipek Jana Luxová Petra Šulcová 《Ceramics International》2021,47(17):24607-24614
A new pyrophosphate(V) of the formula Co5Cr2(P2O7)4 was obtained in the system Co2P2O7–Cr4(P2O7)3 as a result of solid-state reactions taking place between different reactants. The new compound crystallizes in the orthorhombic system and belongs to the family of pyrophosphates of the general formula M52+M23+(P2O7)4 and is probably isostructural with Fe52+Fe23+(P2O7)4. Powder diffraction pattern, infrared spectrum and SEM image of the new compound were presented. As a new potential inorganic pigment, Co5Cr2(P2O7)4 was tested for its thermal stability, particle size distribution and colour properties, which were studied both for powder and after introduction into organic matrix and leadless ceramic glaze. The colour of Co5Cr2(P2O7)4 powder was defined as deep grey with the colour coordinates L*/a*/b* = 60.63/-1.42/-3.41 and according to the hue angle (h° = 247.39°) it belongs to the blue region. Co5Cr2(P2O7)4, with its relatively high thermal stability (t m = 1230 ± 10 °C) and appropriate colour properties, is a good candidate to be used as inorganic pigment for colouring of acrylic paints. In the case of leadless glaze, the obtained compound acts as a dye. 相似文献
94.
Tungsten oxide nanoparticles were synthesized using the sol–gel process and applied for heterogeneous photocatalytic removal of a dye using a 355 nm laser radiation generated from Nd:YAG for the first time. Effect of various parameters, such as calcination temperature, calcination time, catalyst concentration and laser energy on the photocatalytic removal of dye has been investigated. The study showed that almost complete degradation of dye can be achieved within very short time of reaction (within few minutes) in presence of nanocrystalline WO3 under laser irradiation. The removal process obeys first-order kinetics with an appreciable rate constant 0.146 min−1. The main reason of high efficiency is the nanostructure nature of WO3 and the laser as an excitation source as compared with the conventional setups using lamps and conventional microstructure catalysts. 相似文献
95.
J. Weidmann Th. Dittrich E. Konstantinova I. Lauermann I. Uhlendorf F. Koch 《Solar Energy Materials & Solar Cells》1998,56(2):3450
Oxygen- and water-related surface defects on porous TiO2 (anatase) can be well controlled by the oxygen and water partial pressures and therefore such defects are of technological relevance for dye sensitized TiO2 solar cells. We investigated the action of oxygen and water-related surface defects in situ by impedance spectroscopy, photoconductivity, photoluminescence, and optical transmission as well as by characterizing solar cells which were prepared under respective conditions. Oxygen loss from the TiO2 surface leads to electrical doping by Ti3+/oxygen donor states. Such defects create recombination paths for injected electrons back into the electrolyte. Pre-treatment of porous TiO2 by chemisorption of water increases the open circuit voltage of the solar cells without altering the short circuit current. Water-related surface defects decrease the saturation current of the diode, probably by raising the barrier height at the TiO2/electrolyte interface. 相似文献
96.
Toshiko Mizokuro Hiroyuki Mochizuki Nobutaka Tanigaki Takashi Hiraga 《Thin solid films》2008,516(9):2411-2415
We report selective doping of vapor of yellow dye, ferrocenedimethanol into exposed (UV-irradiated) areas of novolac resin films. When vapor of the dye was contacted with micro-patterned resin films containing both exposed and unexposed areas, the dye was doped only into the exposed areas, resulting in fabrication of micro-pattern containing the dye. On the contrary, ferrocene and other ferrocene derivatives were doped both exposed and unexposed areas of the resin. A contact angle measurement of aqueous drops on each dye indicated that the chemical affinity between hydroxyl groups of ferrocenedimethanol and exposed areas of the novolac resin will enhance selective doping of the dye into the exposed areas. 相似文献
97.
染料强度等指标的检测及其在印染生产中的管理 总被引:1,自引:0,他引:1
阐述了染料的标准化问题及其在印染生产中的重要性,提出了染料的标准、检测和应用管理等有关具体措施;并分析讨论了对产品质量、生产成本、经济核算等方面的作用和意义。 相似文献
98.
99.
G. R. R. A. Kumara A. Konno G. K. R. Senadeera P. V. V. Jayaweera D. B. R. A. De Silva K. Tennakone 《Solar Energy Materials & Solar Cells》2001,69(2)
A method is devised for the deposition of CuSCN on ruthenium bipyridyl dye coated nanocrystalline TiO2 films from a solution in n-propyl sulphide. The dye-sensitized solid state photovoltaic cell formed was found to yield higher short-circuit photocurrent, open-circuit voltage and efficiency compared to the cells made with CuSCN by other deposition techniques. Factors affecting the stability of the cell are investigated. 相似文献
100.
K. Petritsch J. J. Dittmer E. A. Marseglia R. H. Friend A. Lux G. G. Rozenberg S. C. Moratti A. B. Holmes 《Solar Energy Materials & Solar Cells》2000,61(1)
We have fabricated organic donor/acceptor solar cells with three different architectures using soluble derivatives (dyes) of the molecular semiconductors phthalocyanine as electron donor (D), i.e. hole transport material and perylene as electron acceptor (A), i.e. electron transport material. These architectures comprise a blend and a double layer structure as well as the only recently reported laminated-device structure. The organic semiconducting films were deposited at room temperature via spin coating from solution. Current–voltage (I/V) characteristics and external quantum efficiency spectra will be discussed. The measured quantum efficiencies reach values between 0.3% and 1.1% with a photoresponse covering the entire spectrum of visible light. Our results show that together with insoluble small molecules (pigments) and conjugated polymers, dye molecules represent a new class of organic semiconducting materials that can be used to manufacture D/A solar cells. 相似文献