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41.
Kati Miettunen Jarkko Etula Tapio Saukkonen Sami Jouttijrvi Janne Halme Jyrki Romu Peter Lund 《Progress in Photovoltaics: Research and Applications》2015,23(8):1045-1056
The main issue in using low cost metals in dye solar cells is the corrosion caused by the liquid electrolyte. Contrary to typical applications of metals, the adverse effects of corrosion in dye solar cells are related to irreversible depletion of charge carriers from the electrolyte rather than consumption of the metal itself. It is calculated that the penetration rate due to corrosion should not exceed 10−4 mpy (a couple of nanometers per year) to ensure device lifetime longer than 1 year. This is 10 000 times slower rate than what is considered to be a general benchmark value for very low corrosion rate in the field of corrosion science and has a major effect on how corrosion should be investigated in the case of dye solar cells. Different methods, their applicability, and limitations to investigate corrosion in dye solar cells are evaluated here. The issue with most techniques is that they can detect metals that are clearly corroding, but they have significant limitations in proving a metal stable. Our investigation shows that the most reliable information on corrosion is obtained from complete dye solar cells that are exposed to working conditions. A combination of color analysis of the electrolyte to such measurement is proposed as a means to extrapolate future performance of the cells and estimate potential lifetimes of the dye solar cells in regards to corrosion. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
42.
Mina Han Ikue Abe Jihun Oh Jaehoon Jung Young Ji Son Jaegeun Noh Mitsuo Hara Takahiro Seki 《International journal of molecular sciences》2022,23(2)
Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials. 相似文献
43.
采用SnCl_2-HCl法对商品皮革深棕染料NR进行降解分析,推断该商品染料为酸性棕75.通过反向合成得到酸性棕75,并通过与商品染料的R_f值、可见吸收曲线、红外光谱图、产品染色性能以及还原裂解产物对比,说明商品皮革深棕染料NR的主体成分结构推断正确. 相似文献
44.
棉纤维与羊毛纤维在结构和性质上的差异,导致了他们染色工艺的不同.通过测试B型活性染料在pH值11和60℃条件下处理30 min后对棉纤维染色的固色率,以及羊毛在相同条件染色后的断裂强度,认为B型活性染料应用于棉/毛织物一浴两步法染色是可行的.通过模拟对棉/毛50150和80/20 2种混纺比织物在一浴两步法染色中pH值的控制,达到了2种纤维混纺织物同色效果. 相似文献
45.
蛋壳膜对有机染料的吸附脱色作用研究 总被引:2,自引:0,他引:2
蛋壳膜是一种大孔型的生物活性吸附材料,具有较大的比表面积。研究了蛋壳膜对有机染料曙红B的吸附脱色作用。试验考察了吸附时间、溶液pH值、温度对吸附脱色的影响。吸附平衡时间为100min;最佳pH值吸附条件为2.0;蛋壳膜对曙红B的吸附量随温度升高而增加。在常温下,蛋壳膜对曙红B的脱色率达95%以上,最大吸附量为40.9mg/g,其吸附行为符合Freundlich吸附等温线。 相似文献
46.
高效液相色谱法测定染发剂中对苯二胺及某些酚类物质的含量 总被引:9,自引:0,他引:9
本文采用了高效液相色谱法测定染发剂中对苯二胺、邻氨基酚、对苯二酚及间苯二酚。该法简便快速 ,检测下限分别为 0 .0 89、0 .2 5、0 .0 0 19和 0 .0 0 33毫克 /克 ,具有良好的精密度和准确度 相似文献
47.
48.
以邻甲氧基苯胺和间苯二胺为主要原料,经磺酰化、酰胺化、脱乙酰基,合成了新型替代致癌染料中间体N,N′-1,3-苯基-二(3-氨基-4-甲氧基)苯磺酰胺,并确定了较佳工艺条件。产品经元素分析、红外、质谱和核磁表征确证了结构。 相似文献
49.
光敏剂诱导化学镀镍的研究 总被引:5,自引:0,他引:5
在酸性化学镀镍镀液中加入光敏剂S,光照下可以实现室温化学镀镍.研究了光敏剂浓度、入射光强度和波长、镍盐和次磷酸根浓度对化学镀镍沉积速度的影响.根据实验结果推测了光敏剂S诱导化学镀镍的反应机理. 相似文献
50.