排序方式: 共有44条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Taniya M. S. K. Pathiranage Dushanthi S. Dissanayake Crystal N. Niermann Yixin Ren Michael C. Biewer Mihaela C. Stefan 《Journal of polymer science. Part A, Polymer chemistry》2017,55(20):3327-3346
Semiconducting polythiophenes display electroactive properties which make them excellent candidates for applications as electroactive materials. Ability to undergo doping and to switch between different oxidation states allow tuning the chemical and physical properties of polythiophenes. Furthermore, the ability to integrate polythiophenes into copolymers, hybrid composites with metals and inorganic materials make them useful in electronic and biomedical applications. The capability to vary the properties of the final material with low production cost and high processability into thin films makes polythiophenes desirable materials for many applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3327–3346 相似文献
5.
Kumari J. M. K. W. Senadeera G. K. R. Weerasinghe A. M. J. S. Thotawatthage C. A. Dissanayake M. A. K. L. 《Journal of Solid State Electrochemistry》2021,25(2):695-705
Journal of Solid State Electrochemistry - Ionically conducting gel polymer electrolytes can be used effectively to improve the problems associated with liquid electrolytes in dye-sensitized solar... 相似文献
6.
T. M. Wijendra Jayalath Bandara Piyasiri Ekanayake M. A. K. Lakshman Dissanayake Ingvar Albinsson Bengt-Erik Mellander 《Journal of Solid State Electrochemistry》2010,14(7):1221-1226
Various iodide ion conducting polymer electrolytes have been studied as candidate materials for fabricating photoelectrochemical
(PEC) solar cells and energy storage devices. In this study, enhanced ionic conductivity values were obtained for the ionic
liquid tetrahexylammonium iodide containing polyethylene oxide (PEO)-based plasticized electrolytes. The analysis of thermal
properties revealed the existence of two phases in the electrolyte, and the conductivity measurements showed a marked conductivity
enhancement during the melting of the plasticizer-rich phase of the electrolyte. Annealed electrolyte samples showed better
conductivity than nonannealed samples, revealing the existence of hysteresis. The optimum conductivity was shown for the electrolytes
with PEO:salt = 100:15 mass ratio, and this sample exhibited the minimum glass transition temperature of 72.2 °C. For this
optimum PEO to salt ratio, the conductivity of nonannealed electrolyte was 4.4 × 10−4 S cm−1 and that of the annealed sample was 4.6 × 10−4 S cm−1 at 30 °C. An all solid PEC solar cell was fabricated using this annealed electrolyte. The short circuit current density (I
SC), the open circuit voltage (V
OC), and the power conversion efficiency of the cell are 0.63 mA cm−2, 0.76 V, and 0.47% under the irradiation of 600 W m−2 light. 相似文献
7.
The addition of water vapor has a strong positive effect on the rate of ethane oxidation at 575°C. This effect is attributed to the role of H2O as a third body in the decomposition of H2O2 to OH radicals. Carbon tetrafluoride likewise enhances the rate of ethane conversion, although not to the extent realized with H2O. A kinetic model, based on known elementary reactions, adequately accounts for the conversions and selectivities observed as a function of H2O pressure, temperature, contact time, and O2 pressure. © 1994 John Wiley & Sons, Inc. 相似文献
8.
K. S. Perera M. A. K. L. Dissanayake S. Skaarup K. West 《Journal of Solid State Electrochemistry》2008,12(7-8):873-877
Polyacrylonitrile (PAN)-based polymer electrolytes have obtained considerable attention due to their fascinating characteristics such as appreciable ionic conductivity at ambient temperatures and mechanical stability. This study is based on the system PAN–ethylene carbonate (EC)–propylene carbonate (PC)–lithium trifluoromethanesulfonate (LiCF3SO3). The composition 15 mol% PAN–42 mol% EC–36 mol% PC–7 mol% LiCF3SO3 has shown a maximum room temperature conductivity of 1.2?×?10?3 S cm?1. Also, it was possible to make a thin, transparent film out of that composition. Cells of the form, Li/PAN–EC–PC–LiCF3SO3/polypyrrole (PPy)–alkylsulfonate (AS) were investigated using cyclic voltammetry and continuous charge–discharge tests. When cycled at low scan rates, a higher capacity could be obtained and well-defined peaks were present. The appearance of peaks elucidates the fact that redox reactions occur completely. This well proves the reason for higher capacity. The average specific capacity was about 43 Ah kg?1. Cells exhibited a charge factor close to unity during continuous charging and discharging, indicating the absence of parasitic reactions. 相似文献
9.
McHedlov-Petrossyan NO Bryleva EY Vodolazkaya NA Dissanayake AA Ford WT 《Langmuir : the ACS journal of surfaces and colloids》2008,24(11):5689-5699
Aqueous solutions of four cationic poly(propylenimine) low-generation dendrimers of different architecture and hydrophobicity have been examined as media for acid-base reactions of indicator dyes. The cationic dendrimers in solution can be considered as oligomers of cationic polyelectrolytes, or surfactant-like species, able to form micelles through self-association or sometimes even as unimolecular micelles. The dendrimers influence the ionization constants, tautomeric equilibria, and absorption/emission/excitation spectra of indicator dyes. The p K a values of the majority of the indicator dyes decrease in dendrimer solutions, often by 1-2 p K a units, similar to effects registered in micellar solutions of cationic surfactants. Analogously, the shifts of absorption band maxima indicate that the microenvironments of the dyes bound to the dendrimers are less polar than in water. However, some spectral effects denote the specificity of the dendrimers. The greatest difference between the dendrimers and spherical surfactant micelles is revealed by kinetic processes, especially of bromophenol blue alkaline fading in a dendrimer solution but not in a micellar surfactant solution. Within the dendrimer series, the most significant differences were observed for substances possessing n-dodecyl tails on the one hand and those without such hydrophobic portions on the other. For the last-named, the decrease in p K a's of indicators, band shifts of their anions, and in particular displacement of tautomeric equilibria compared with aqueous solutions are much smaller than for more hydrophobic dendrimers. 相似文献
10.
T. M. W. J. Bandara B.-E. Mellander I. Albinsson M. A. K. L. Dissanayake H. M. J. C. Pitawala 《Journal of Solid State Electrochemistry》2009,13(8):1227-1232
The anion-conducting polymer electrolyte polyethylene oxide (PEO)/ethylene carbonate (EC)/Pr4N+I−/I2 is a candidate material for fabricating photo-electrochemical (PEC) solar cells. Relatively high ionic conductivity values
are obtained for the plasticized electrolytes; at room temperature, the conductivity increases from 7.6 × 10−9 to 9.5 × 10−5 S cm−1 when the amount of EC plasticizer increases from 0% to 50% by weight. An abrupt conductivity enhancement occurs at the melting
of the polymer; above the melting temperature, the conductivity can reach values of the order of 10−3 S cm−1. The melting temperature decreases from 66.1 to 45.1 °C when the EC mass fraction is increased from 0% to 50%, and there
is a corresponding reduction in the glass transition temperature from −57.6 to −70.9 °C with the incorporation of the plasticizer.
The static dielectric constant values, , increase with the mass fraction of plasticizer, from 3.3 for the unplasticized sample to 17.5 for the 50% EC sample. The
dielectric results show only small traces of ion-pair relaxations, indicating that the amount of ion association is low. Thus,
the iodide ion is well dissociated, and despite its large size and relatively low concentration in these samples, the iodide
ion to ether oxygen ratio is 1:68, a relatively efficient charge carrier. A further enhancement of the ionic conductivity,
especially at lower temperatures, is however desired for these applications. 相似文献