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1.
Various ordered structures of crystalline three-dimensional (3D) cubic, 2D columnar or 1D lamellar mesophases have been facilely achieved through host–guest interactions of electrically neutral host tris(18-crown-6)triphenylene and guest potassium sulfonates with alkyl tails of variant number and length. The convenient construction of functionalised ionic complexes and the flexibility of such a supramolecular approach offer a wide variety of possibilities to prepare various ordered functional soft materials, especially those in their 2D ordered columnar liquid crystalline mesophases may serve as promising electron and ion dual-channel transport organic electronic materials. 相似文献
2.
本文研究了光谱增感染料的结构对立方体卤化银乳剂的感光性能的影响,并利用反射光谱和彩色分析荧光电镜研究了染料在卤化银微晶上的聚集态和J 聚集体的相对尺寸,通过测定乳剂离子电导率研究了染料的结构对乳剂离子电导率的影响.实验结果表明:本文中所用的九个染料不管是增感还是减感染料都能在立方体卤化银乳剂上形成J 聚集态;对噻碳菁染料而言,其5位上无论是吸电子基团还是推电子基团的染料形成的J 聚集体的平均尺寸皆较未取代染料的大,其增感效果也较好;苯环5位上吸电子基取代或平面性好的噻碳菁染料可提高立方体AgBrI乳剂的离子电导率,证明它们的增感效果也好;6位硝基取代的吲哚碳菁染料是典型的减感染料,其在立方体乳剂上所形成的J 聚集体较小,但是对乳剂的离子电导无影响.此外,本文还试图对不对称插烯菁染料Dye9使立方体AgBrI乳剂减感的作用进行了解释 相似文献
3.
Rongxiang He Prof. Aifeng Lv Xingyu Jiang Chang Cai Yazhou Wang Prof. Wan Yue Prof. Lizhen Huang Prof. Xue-Bo Yin Prof. Lifeng Chi 《Angewandte Chemie (International ed. in English)》2023,62(37):e202304549
Hydrophobic conjugated polymers have poor ionic transport property, so hydrophilic side chains are often grafted for their application as organic electrochemical transistors (OECTs). However, this modification lowers their charge transport ability. Here, an ionic gel interfacial layer is applied to improve the ionic transport while retaining the charge transport ability of the polymers. By using the ionic gels comprising gel matrix and ionic liquids as the interfacial layers, the hydrophobic polymer achieves the OECT feature with high transconductance, low threshold voltage, high current on/off ratio, short switching time, and high operational stability. The working mechanism is also revealed. Moreover, the OECT performance can be tuned by varying the types and ratios of ionic gels. With the proposed ionic gel strategy, OECTs can be effectively realized with hydrophobic conjugated polymers. 相似文献
4.
I. R. Rubin V. A. Lobatch B. V. Shulgin 《International journal of quantum chemistry》1987,32(2):193-205
The recently developed crystalline cluster method within the framework of the Johnson multiple scattering technique was successfully used in calculations of ionic cubic crystals and the defects with a cubic symmetry. In this paper a simple way of extension of the method to noncubic systems by a partial elimination of “muffin-tin” approximation (MTA ) is proposed. The procedure suggested does reduce the intermediate integrals to the one-dimensional ones, and they are calculated analytically. It is supposed that an approach of taking into account the nonspherical shape of the potential inside the “muffin-tin” (MT ) spheres will be effective in crystals with an ionic type of chemical bond. 相似文献
5.
Dr. Qing Xu Dr. Shanshan Tao Dr. Qiuhong Jiang Prof. Donglin Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4587-4593
A strategy based on covalent organic frameworks for ultrafast ion transport involves designing an ionic interface to mediate ion motion. Electrolyte chains were integrated onto the walls of one-dimensional channels to construct ionic frameworks via pore surface engineering, so that the ionic interface can be systematically tuned at the desired composition and density. This strategy enables a quantitative correlation between interface and ion transport and unveils a full picture of managing ionic interface to achieve high-rate ion transport. Moreover, the effect of interfaces was scaled on ion transport; ion mobility is increased in an exponential mode with the ionic interface. This strategy not only sets a benchmark system but also offers a general guidance for designing ionic interface that is key to systems for energy conversion and storage. 相似文献
6.
Qing Xu Shanshan Tao Qiuhong Jiang Donglin Jiang 《Angewandte Chemie (International ed. in English)》2020,59(11):4557-4563
A strategy based on covalent organic frameworks for ultrafast ion transport involves designing an ionic interface to mediate ion motion. Electrolyte chains were integrated onto the walls of one‐dimensional channels to construct ionic frameworks via pore surface engineering, so that the ionic interface can be systematically tuned at the desired composition and density. This strategy enables a quantitative correlation between interface and ion transport and unveils a full picture of managing ionic interface to achieve high‐rate ion transport. Moreover, the effect of interfaces was scaled on ion transport; ion mobility is increased in an exponential mode with the ionic interface. This strategy not only sets a benchmark system but also offers a general guidance for designing ionic interface that is key to systems for energy conversion and storage. 相似文献
7.
本文研究了小颗粒(<0.2μm)立方体乳剂的不同碘含量及不同碘分布对乳剂感光度、离子电导和光电导的影响.结果表明,在一个较小的碘含量范围内,当碘的分布基本相同时,乳剂感光度与离子电导随碘含量增加而增加,在本实验条件下产生这种影响的碘的摩尔分数范围为0~1%.而乳剂的光电子寿命在实验范围内一直是增加的. 相似文献
8.
Coupled Electrical Conduction in Coordination Polymers: From Electrons/Ions to Mixed Charge Carriers
The coupled transport of ions and electrons is of great potential for next‐generation sensors, energy storage and conversion devices, optoelectronics, etc. Coordination polymers (CPs) intrinsically have both transport pathways for electrons and ions, however, the practical conductivities are usually low. In recent years, significant advances have been made in electronic or ionic conductive coordination polymers, which also results in progress in mixed ionic‐electronic conductive coordination polymers. Here we start from electronic and ionic conductive CPs to mixed ionic‐electronic conductive CPs. Recent advances in the design of mixed ionic‐electronic conductive CPs are summarized. In addition, devices based on mixed conduction are selected. 相似文献
9.
Seo SJ Woo JJ Yun SH Lee HJ Park JS Xu T Yang TH Lee J Moon SH 《Physical chemistry chemical physics : PCCP》2010,12(46):15291-15300
Interfacial resistances between the polymer electrolyte membrane (PEM) and catalyst layer (CL) in membrane-electrode assemblies (MEAs) have yet to be systematically examined in spite of its great importance on the fuel cell performance. In order to investigate ionic transport through the PEM/CL interface, the symmetrical impedance mode (SIM) was employed in which the same type of gas was injected (H(2)/H(2)). In this study, the ionic transport resistance at the interface was controlled by the additionally sprayed outer ionomer on the surface of each CL. Effectiveness of the outer ionomer on ionic transport at the interface was quantitatively explained by the reduced contact, proton hydration, and charge transport resistances in the SIM. To characterize the ionic transport resistance, the concept of total resistance (R(tot)) in the SIM was introduced, representing the overall ohmic loss due to proton transport in an MEA. This concept was successfully supported via an agreement of the interpretation and the linear correlation that was obtained between the admittance (1/R(tot)) and the performance of a fuel cell in the ohmic loss region. This correlation will enable researchers to predict the performance of a fuel cell under the influence of proton transport by examining the R(tot) in the SIM. 相似文献
10.
Beu TA 《The Journal of chemical physics》2011,135(4):044516
The present investigations continue previous research on transport in aqueous ionic solutions through carbon nanotubes. Specifically, the effects of the nanotube radius, solute concentration, and applied external electric fields on the transport properties are investigated in terms of mobilities, currents, and pairing times of the solute ions. The simulated transport features are corroborated with general theoretical results of nanofluidics (such as the linear log-log regime of the nanochannel conductance as function of the solute concentration and the current-voltage curve of the channel). Discontinuities in the partial ionic currents are explained on the basis of a recent theoretical model of quantized ionic conductance in nanopores, developed by Zwolak et al. Correlations between the structural and dynamic properties are established, linking causally the highly structured spatial density profiles, the ion pairing phenomenon and the ionic currents. 相似文献
11.
Schmuhl R Keizer K van den Berg A ten Elshof JE Blank DH 《Journal of colloid and interface science》2004,273(1):331-338
The electric field-driven transport of ions through supported mesoporous gamma-alumina membranes was investigated. The influence of ion concentration, ion valency, pH, ionic strength, and electrolyte composition on transport behavior was determined. The permselectivity of the membrane was found to be highly dependent on the ionic strength. When the ionic strength was sufficiently low for electrical double-layer overlap to occur inside the pores, the membrane was found to be cation-permselective and the transport rate of cations could be tuned by variation of the potential difference over the membrane. The cation permselectivity is thought to be due to the adsorption of anions onto the pore walls, causing a net negative immobile surface charge density, and consequently, a positively charged mobile double layer. The transport mechanism of cations was interpreted in terms of a combination of Fick diffusion and ion migration. By variation of the potential difference over the membrane the transport of double-charged cations, Cu2+, could be controlled accurately, effectively resulting in on/off tunable transport. In the absence of double-layer overlap at high ionic strength, the membrane was found to be nonselective. 相似文献
12.
Transmembrane transport of ammonia and carbon dioxide through perfluorosulfonic membranes in ionic forms of transition metals was studied in a wide temperature interval. The different patterns of the temperature plots of the permeability coefficient of ammonia were found for different ionic forms of the membrane. An increase in the ammonia permeability with an increase in the moisture contents of the membrane also depends on its ionic form. The effects observed are explained by the different structures of water—ammonia complexes formed with metal ions. The mechanism of transmembrane transport of ammonia through perfluorosulfonic membranes in various ionic forms is discussed. 相似文献
13.
Enyi Hu Jun Wang Longqing Ma Muhammad Yousaf Dr. Faze Wang Bin Zhu Wenxiu Yang Peter Lund 《Chemphyschem》2023,24(3):e202200656
Electrochemical properties of metal oxide have a strong correlation with the crystalline structures. In this work, the effect of calcination temperature on the phase evolution and electrochemical properties of Sm2O3 was systematically evaluated. The results demonstrate that the sample calcinated at 700 °C (SM-700) is composed of a pure cubic phase while it begins to convert into a monoclinic phase at a temperature above 800 °C and fully converts into a monoclinic phase at 1100 °C. Moreover, the evolution process causes atomic redistribution, and more oxygen vacancies are formed in cubic phase Sm2O3, contributing to the improved ionic conductivity. The ionic conductivity of 0.138 S cm−1 and maximum power density of 895 mW cm−2 at 520 °C are achieved using SM-700 as electrolyte for protonic ceramic fuel cell (PCFC). The cubic structure remains stable in the durability testing process and the SM-700 based fuel cell delivers enhanced stability of 140 mW cm−2 for 100 h. This research develops a calcination evolution process to improve the ionic conductivity and fuel cell performance of the Sm2O3 electrolyte for stable PCFC. 相似文献
14.
Size-dependent 3D superlattices have been fabricated from ZnO nanocrystals capped with ionic liquid components; on the basis of X-ray diffraction, two packing modes, that is, hexagonal and face-centered cubic close packings, have been discovered for the superlattices consisting of the ZnO nanocrystals as building blocks. 相似文献
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16.
Ternary cubic phases containing ionic liquid 总被引:1,自引:0,他引:1
The phase diagram of 1-butyl-3-methylimidazolium tetrafluoroborate (bmim-BF(4)) in aqueous solutions of oleyl polyoxyethylene (20) ether (C(18:1)E(20)) was determined at 25 degrees C by a combination of visual inspection and small-angle X-ray scattering (SAXS). The micellar cubic Im3m liquid crystalline phase found in the ternary system was investigated by means of SAXS and rheological techniques. The cubic samples show highly elastic gel-like properties indicated by their mechanical and discrete relaxation spectra. Moreover at a constant C(18:1)E(20)/bmim-BF(4) ratio, with decreasing water content the network strength increases. The internal structure apparently becomes more stable, as indicated by an increase in the storage and loss moduli and a decrease in the lattice parameter alpha and interfacial area of per surfactant a(S). Furthermore, investigations on the representative micellar Im3m cubic phases formed in a relatively hydrophobic ionic liquid bmim-PF(6) with C(18:1)E(20) and water ternary system (P(1)), a C(18:1)E(20)/water binary system (J(1)), and C(18:1)E(20)/water/bmim-BF(4) system (B(1)) were made in comparison. It can be clearly seen that appreciably different mechanical spectra and relaxation spectra are shown by the cubic phases investigated. B(1) exhibits a typical gel-like dynamic rheogram while P(1) exhibits fluid-like viscoelastic properties to some extent, and J(1) shows traits of the general Maxwell model. These differences are analyzed through SAXS data as the employment of ionic liquids and their different location in the cubic phases. 相似文献
17.
利用微机控制平衡双注法在不同pAg条件下,成功地制备了三种单分散十四面体AgBr(Ⅰ)主晶并随后在其(111)面上外延淀积AgCl而获得三种单分散AgCl,AgBr(Ⅰ)外延立方颗粒乳剂,外延颗粒介电频谱曲线出现明显分立的双峰,分别相应于其中AgBr(Ⅰ)和AgCl两相对离子电导的贡献,主晶及外延颗粒的离子电导均随制备时的pAg变化,但变化规律不同。 相似文献
18.
The objective was to examine how a bicontinuous cubic phase influences the diffusion and electrochemical activity of dissolved molecules. The cubic phase is a structure with three-dimensional continuous channels of water separated by an apolar membrane. A redox active molecule can dissolve in three different environments. A hydrophobic molecule will prefer the interior of the membrane, a hydrophilic molecule will prefer the water channels, and an amphiphilic molecule will be situated with its headgroup at the surface of the membrane and its tail in the interior. The electrochemical activity was measured with cyclic voltammetry and the transport behavior with chronocoulometry. All the molecules were redox active in the cubic phase; that is, all the molecules could reach the surface of the electrode and react. The cubic phase made the kinetics of the charge transfer slower, showing a quasi-reversible behavior. The reason may be that a layer of the membrane adheres to the hydrophobic electrode surface. The diffusion experiment showed that the diffusion was slower than in solution. The molecules that were restricted to diffuse within the membrane gave particularly low mass transport rates. 相似文献
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20.
Carsten Korte N. Schichtel D. Hesse J. Janek 《Monatshefte für Chemie / Chemical Monthly》2009,37(8):1069-1080