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91.
The cloud point of nonionic surfactant (Triton X-114) in ionic liquid ([Bmim]Cl) aqueous solution exhibits as increase and then decrease and increase again with the increase of ionic liquid (IL) content, which is the origin of an IL–nonionic surfactant aqueous two-phase system. The nonionic surfactant-rich phase coexists with a high content of IL aqueous solution phase in the IL–nonionic surfactant aqueous two-phase system. The partitioning of various ionic dyes indicates that anionic species exhibit a high partitioning coefficient between the IL-rich phase and the nonionic surfactant-rich phase. 相似文献
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93.
The application of nickel based earth abundant inorganic solids as catalysts in xanthene dye sensitized systems was evaluated for photocatalytic H2 production from water. The introduction of heterogeneous nanoparticles into molecular systems as catalysts is the conceptual begin to broaden the construction of photocatalytic H2 production systems. A series of Ni based inorganic nanoparticles, including Ni metal, NiO, NiS and NiSe, are capable of producing H2 from triethanolamine sacrificial aqueous solution when photosensitized by xanthene dyes. NiS catalysts synthesized from different methods were also evaluated for H2 production performance. The best H2 production result is obtained with the use of Erythrosin Y as the photosensitizer and NiS synthesized in ethylene glycol as the catalyst. This system is active even under photons with wavelengths longer than 520 nm with a H2 production of 2.5 mmol within 26 h of irradiation from a 300 W Xenon lamp. Meanwhile, it can generate over 4.2 mmol of H2 within 16 h of irradiation with a 440 nm long-pass cut-off filter. Within the visible light range we examined, the highest quantum efficiency is around 15% at 520 nm. The high activity of NiS could be contributed by its high electrochemical activity, metallic nature, unsaturated Ni environment and suitable Fermi energy level. These hybrid systems consist of earth abundant elements, and the catalyst is photostable and recyclable compared to homogeneous metal complex catalyst. 相似文献
94.
The use of graphene to bridge TiO2 particles in the photoanode of dye‐sensitized solar cell for reduced electrical resistance has been investigated. The difficulty in dispersing graphene in TiO2 paste was overcome by first dispersing graphene oxide (GO) into the TiO2 paste. The GO was then reduced to graphene after the sintering of TiO2. This is shown through transmission electron microscopy and X‐ray photoelectron spectroscopy analysis. Cell performance was evaluated using a solar simulator, incident photon to electron conversion efficiency, intensity modulated photocurrent/photovoltage spectroscopy under blue light, and electrochemical impedance spectroscopy. Depending on the amount of graphene in the photoanode, the cell performance was enhanced to different degrees. A maximum increase of 11.4% in the cell efficiency has been obtained. In particular, the inclusion of graphene has reduced the electron diffusion time by as much as 23.4%, i.e. from 4.74 to 3.63 ms and increased the electron lifetime by as much as 42.3%, i.e. from 19.58 to 27.85 ms. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
95.
Efficient dye sensitized solar cells (DSSCs) are developed using phenoxazine (POZ) based organic dye (WS5) and graphene nanosheets (GNs) counter electrode (CE). Being organic, both these materials are used together to explore compatibility of organic materials in current DSSCs. Organic dye with POZ moiety is synthesized and graphene oxide nanosheets (GONs) are spin coated on FTO glass and thermally reduced afterwards. To increase the performance of WS5 through decreased dye aggregation, deoxycholic acid (DCA) is added to it. The results of adding DCA are observed and compared using UV–Vis spectroscopy, external quantum efficiency (EQE), electrochemical impedance spectroscopy (EIS) and photovoltaic conversion efficiency (PCE). Prepared organic dye based DSSC cell results in a high PCE of 6.61%. The optimized WS5 dye and GNs CE, shows PCE of 5.77% and the GNs CE compared to Pt CE results in almost identical charge transfer resistance value at the CE/electrolyte interface. Low cost of this designed organic dye and GNs and the PCE results indicate that this combination may result in the reduction of cost of current DSSCs and the realization that expensive and rare inorganic materials can be replaced with organic ones in future. 相似文献
96.
采用升华牢度均为3.0级的分散黄E-RG-2染料混合物、分散红M-3B染料混合物和分散蓝2BLN染料作为三原色,对中浅色涤纶面料染色,在受热定型时解决了因各染料成分升华不一致而导致严重色光变化的问题,提高了成品率。该三原色进一步拼混还可获得一种分散灰SE-M染料混合物,同样也具有升华牢度的平衡性和受热定型时色光的稳定性。 相似文献
97.
The effect of unit k/s calculation and spectral overlapping on the performance of color matching
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There are several approaches to dyeing recipe formulation in the textile industry, because the accuracy of computer recipe prediction is not very high. There are several theories such as colorimetric and spectrophotometeric appraches on color reception. This work addressed the effect of the calibration method as the calculation of unit k/s and spectral overlapping of the components of the mixture on the accuracy of recipe prediction in dyeing nylon with acid dye. To this aim, the unit k/s was calculated using single and binary mixture samples. Two types unit k/s were used for the recipe prediction of ternary mixture dyed samples with low and high overlapping reflectance spectra. The obtained results indicated that the unit k/s of single component differed from the unit k/s of bicomponent mixture. The accuracy of recipe prediction using unit k/s of single component was less than that of the binary mixture. However, the performance of the recipe prediction of high level overlapping was found to be more than that of the low level overlapping mixture. Subsequently, the accuracy of color matching depended on the reflectance spectra similarity (spectral overlapping) of the components of the mixture. 相似文献
98.
The use of the laser beam‐induced current (LBIC) technique in photovoltaic devices is widespread, but its use in photoelectrochemical cells, such as dye‐sensitized solar cells (DSSCs), is limited due to the configuration of these devices. The main reason is the very slow response time of DSSCs in the decay process, and therefore LBIC scans take too long to perform. We have designed a procedure published in the literature to correct the photocurrent values obtained by the LBIC technique, based on an algorithm that uses a decreasing mono‐exponential model. This work presents a study of the decay measurements in DSSCs using several functions, in order to improve the algorithm designed. It concludes that functions such as a decreasing bi‐exponential or Becquerel function generate better fits to experimental data. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
99.
100.
Palladium-catalysed amination of bromofluorans and an investigation of their thermochromic behaviour
The palladium-catalysed amination of readily accessible bromofluorans and bromobenzo[a]fluorans has been accomplished with a series of anilines and morpholine. The resulting aminofluorans generated intense black shades upon formulation in methyl stearate containing bisphenol A. The route provides an alternative approach to various amino substituted fluorans without the need of a series of individual diphenylamine intermediates. 相似文献