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排序方式: 共有802条查询结果,搜索用时 15 毫秒
51.
《Advanced Powder Technology》2022,33(1):103367
The rapid manufacturing of high-efficiency dye-sensitized solar cells (DSSCs) is limited by the slow dye adsorption on TiO2 nanoparticles (NPs)-accumulated photoelectrode using conventional dip-coating process. Therefore, we aim to accelerate the adsorption of dyes that are attached on TiO2 NPs by employing an aerosol impactor. Herein the aerosolized dyes are designed to get deposited rapidly on the TiO2 NPs-accumulated photoelectrode. In addition, to effectively trap the irradiated sunlight in DSSCs, we assemble the photoelectrodes incorporated with bilayered TiO2 thin films comprising small TiO2 NPs-based underlayer and large TiO2 NPs-based overlayer as dye-supporting and light-scattering mediums, respectively. Furthermore, the effects of dye aerosol impaction and TiO2 stacking structures on the efficiency of DSSCs are examined. The power conversion efficiency (PCE) of DSSCs comprising a N719 dye-supporting layer treated with dip-coating process was determined as ~ 5.67%; however, when the bilayered TiO2 thin films with an optimized thickness ratio of light-scattering overlayer and dye-supporting underlayer were coated with N719 dyes using dye aerosol impactor, the resulting PCE increased to ~ 7.46%. This suggests that the photovoltaic characteristics of DSSCs can be enhanced considerably using the effective TiO2 NP stacking structures coated with rapid, uniform, and strong aerosol dye adsorption throughout the TiO2-based photoelectrodes. 相似文献
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53.
Poly(ethylene terephthalate), which had been dyed at 0.5, 1.0 and 2.0% omf depths of shade using three disperse dyes, was reduction cleared using a traditional, four-stage process that comprised two water rinses at 40 °C, treatment with aq Na2CO3/Na2S2O4 at 60 °C and one cold water rinse. A novel, two-stage wash-off method was also employed that consisted of treatment with damp nylon beads and surfactant at 70 °C and one cold water rinse. In terms of fastness to repeated washing at 60 °C and colorimetric characteristics, the traditional, four-stage reduction clearing treatment using aq., alkaline Na2S2O4 could be replaced by the two-stage, bead wash-off with detergent at 70 °C. As the detergent-based, bead wash-off process used lower amounts of water than reduction clearing and did not employ sodium dithionite, it avoided the environmentally unacceptable generation of aromatic amines in the case of the reduction clearing of azo dyes. Calculations indicated that considerably less heat energy was consumed in bead wash-off than reduction clearing not only because two, rather than four stages were involved but also since the bead process used only a 2:1 water:fibre ratio rather than the 20:1 liquor ratio employed in the reduction clear process; also, the much lower specific heat capacity of nylon than water meant that much less heat was required to heat the beads. The beads adsorbed vagrant disperse dye during wash-off, thereby offering the potential of a lower effluent load compared to a traditional reduction clearing treatment for disperse dyes on polyester. 相似文献
54.
Mariana Beija Marie-Thérèse Charreyre José M.G. Martinho 《Progress in Polymer Science》2011,36(4):568-602
Dye-labelled polymer chains are extremely useful in many fields, such as optical imaging, signal amplification in biological diagnostics, light-harvesting and photochromic materials as well as in fluorescence studies about intra- and inter-molecular polymer chain associations, conformations and dynamics of polymer chains. However, in many cases, it is particularly useful that the dye is localized at a specific site, such as the chain-end or the junction between blocks. With the development of living/controlled polymerization techniques, end- and junction-functionalized polymers can be prepared with controlled molecular weights from a huge variety of monomers. This review highlights the state of the art in the strategies leading to one and only one precisely localized dye per polymer chain. Such dye can be introduced at three different steps of the polymerization: i) at the very beginning via the initiator or a chain transfer agent, ii) during polymerization via a functional monomer or a quencher, or iii) after polymerization via covalent binding of a dye-derivative. 相似文献
55.
Siqi Zheng Shuxian Shi Yuzheng Xia Qijiayu Wu Zhiqiang Su Xiaonong Chen 《应用聚合物科学杂志》2010,118(2):671-677
A kind of thermo‐sensitive macromonomer, styrene‐terminated poly(N‐isopropylacrylamide‐butyl acrylate) [P(NIPAm‐BA)] has been synthesized in this work. With the help of ultraviolet spectrum (UV), proton nuclear magnetic resonance (1H‐NMR), potentiometric titration and dynamic light scattering (DLS), the molecular structure, thermo‐sensitive characteristics, and micellization behaviors of this kind of macromonomer have been investigated. The obtained results demonstrate that, the molecular structure of thermo‐sensitive macromonomer, including the content of comonomer unit on the backbones and the variety of terminal groups, has great influence on its low critical solution temperature (LCST) and critical micelle concentration (CMC). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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57.
K.A.T. Amalka Perera S. Gaveshana Anuradha G.R. Asoka Kumara M. Lal Paranawitharana R.M. Gamini Rajapakse H.M.N. Bandara 《Electrochimica acta》2011,(11):19
Design, Development, fabrication and investigation of the I–V characteristics of the DSSC based on interconnected 15 nm SnO2 nanoparticles covered with a nano-scale thin layer of CaCO3 are described. The presence of CaCO3 has been confirmed by its characteristic XRD pattern and EDX plots. The thickness of the protective layer can be conveniently controlled by the molar ratio of SnO2:CaCO3 used in the preparation of the thin film and the optimum conditions for best performance of the DSSC are presented together with possible explanations for the variations observed when the molar ratio is changed. An optimum light-to-electricity conversion efficiency of 5.4% in the presence of a layer of CaCO3 has been obtained which is 3.2 times enhancement over the cell prepared without CaCO3. The characterization of the surface using different techniques is explained. 相似文献
58.
介绍了汽巴克隆HW型活性染料替代硫化染料于灯芯绒染色,提高染色牢度及通过优选固色液处方提高该染料固色率的情况。 相似文献
59.
MnO2 nanorods were synthesized by mechanochemical processing with subsequent heat treatment and their photocatalytic activity was studied on the decolourization of aqueous solution of Rhodamine B at different pH levels. A solid state redox reaction 2KMnO4 + MnCl2 → 3MnO2 + 2KCl + O2 was activated during mechanical milling. Excess KCl salt was added in the starting powder mixture to prevent agglomeration of MnO2 nanoparticles. The milling resulted in the production of amorphous MnO2 nanoparticles with a high surface area of 204 m2 g?1. Crystalline MnO2 nanorods of diameters about 15–20 nm were produced by heating the as-milled powder at 350 °C for 1 h in air. Amorphous MnO2 nanoparticles showed higher degradation rate of Rhodamine B than crystalline MnO2 nanorods under simulated sunlight. The degradation rate was higher under acidic conditions. This work demonstrates the potential for cost effective, green and scalable synthesis of MnO2 nano-catalysts for environmental applications. 相似文献
60.
Daniela P. F. Bonfim Cssia S. Santana Marcelo S. Batista Demian P. Fabiano 《化学工程与技术》2019,42(4):882-888
CuO/[Si]MCM‐41 catalysts with various Si/Cu molar ratios were prepared and characterized by X‐ray diffraction, nitrogen physisorption, temperature‐programmed reduction by H2, and UV‐vis and Raman spectroscopy. The effects of copper loading and pH on their activity in the decolorization of methyl orange were studied in a heterogeneous Fenton‐like process. With decreasing Si/Cu ratio, dye decolorization increased from 18 to 75 % at pH 3. CuO/[Si]MCM‐41 catalysts showed 75, 50, and 40 % conversion of methyl orange at pH 3, 5, and 7, respectively. This is a significant improvement to Fenton‐like reactions involving copper, and thus CuO/[Si]MCM‐41 catalysts are quite promising for pollutant degradation. 相似文献