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51.
Dr. Chih‐Min Wang Li‐Wei Lee Tsung‐Yuan Chang Yen‐Chieh Chen Prof. Hsiu‐Mei Lin Prof. Kuang‐Lieh Lu Prof. Kwang‐Hwa Lii 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):1878-1881
An organic–inorganic hybrid zinc phosphate with 28‐ring channels was synthesized by use of an organic ligand instead of organic amine template under a hydro(solvo)thermal condition. This crystalline zinc phosphate contains large channels constructed from 28 zinc and phosphate tetrahedral units. The walls of the channels consist of two types of zincophosphate chains, in which the Zn atoms are coordinated by 2,4,5‐tri(4‐pyridyl)‐imidazole ligands as pendent groups. This compound exhibits yellow emission and interesting properties of removing cobalt, cadmium, and mercury cations from aqueous solution. A new two‐dimensional organic–inorganic hybrid zincophosphate was also obtained by changing the solvent mixture ratios in the synthesis. 相似文献
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Synthesis of Mesoporous Wall‐Structured TiO2 on Reduced Graphene Oxide Nanosheets with High Rate Performance for Lithium‐Ion Batteries 下载免费PDF全文
Mengmeng Zhen Meiqing Sun Prof. Guandao Gao Prof. Lu Liu Prof. Zhen Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5317-5322
Mesoporous wall‐structured TiO2 on reduced graphene oxide (RGO) nanosheets were successfully fabricated through a simple hydrothermal process without any surfactants and annealed at 400 °C for 2 h under argon. The obtained mesoporous structured TiO2–RGO composites had a high surface area (99 0307 m2 g?1) and exhibited excellent electrochemical cycling (a reversible capacity of 260 mAh g?1 at 1.2 C and 180 mAh g?1 at 5 C after 400 cycles), demonstrating it to be a promising method for the development of high‐performance Li‐ion batteries. 相似文献
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Size,Charge, and Stability of Fully Serine‐Based Catanionic Vesicles: Towards Versatile Biocompatible Nanocarriers 下载免费PDF全文
Dr. Sandra G. Silva Prof. M. Luísa C. do Vale Prof. Eduardo F. Marques 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):4092-4101
Vesicles based on mixed cationic and anionic surfactants (catanionic vesicles) offer a number of advantageous colloidal features over conventional lipid‐based vesicles, namely spontaneity in formation, long‐term stability, and easy modulation of size and charge. If biocompatibility is added through rational design of the chemical components, the potential for biorelated applications further emerges. Here, we report for the first time on two catanionic vesicle systems in which both ionic amphiphiles are derivatized from the same amino acid—serine—with the goal of enhancing aggregate biocompatibility. Phase behavior maps for a mixture with chain length symmetry, 12Ser/12‐12Ser, and another with asymmetry, 16Ser/8‐8Ser, are presented, for which regions of vesicles, micelles, and coexisting aggregates are identified. For the asymmetric mixture, detailed phase behavior and microstructure characterization have been carried out based on surface tension, light microscopy, cryo‐SEM, cryo‐TEM, and dynamic light scattering analysis. Vesicles are found with tunable mean size, pH, and zeta potential. Changes in aggregate shape with varying composition and the effect of preparation methods and aging on vesicle features and stability have been investigated in detail. The results are discussed in the light of self‐assembly models and related catanionic systems reported before. A versatile system of robust vesicles is thus presented for potential applications. 相似文献
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Study of spatial inhomogeneity in inverted all‐polymer solar cells: Effect of solvent and annealing 下载免费PDF全文
Andrea Perulli Sandro Lattante Anna Persano Adriano Cola Massimo Di Giulio Marco Anni 《Journal of Polymer Science.Polymer Physics》2015,53(11):804-813
The efficiency optimization of bulk heterojunction solar cells requires the control of the local active materials arrangement in order to obtain the best compromise between efficient charge generation and charge collection. Here, we investigate the large scale (10–100 μm) inhomogeneity of the photoluminescence (PL) and the external quantum efficiency (EQE) in inverted all‐polymer solar cells (APSC) with regioregular poly(3‐hexylthiophene) (P3HT):poly(9,9‐dioctylfluorene‐co‐benzothiadiazole) (F8BT) active blends. The morphology and the local active polymer mixing are changed by depositing the active layer from four different solvents and by thermal annealing. The simultaneous PL and EQE mapping allowed us to inspect the effects of local irregularities of active layer thickness, polymer mixing, polymer aggregation on the charge generation and collection efficiencies. In particular, we show that the increase of the solvent boiling point affects the EQE non‐uniformity due to thickness fluctuations, the density non‐uniformity of rrP3HT aggregate phase, and the blend components clustering. The thermal annealing leads to a general improvement of EQE and to an F8BT clustering in all the samples with locally decrease of the EQE. We estimate that the film uniformity optimization can lead to a total EQE improvement between 2.7 and 6.3 times. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 804–813 相似文献
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Understanding and control of the surface properties such as molecular orientations are of great importance in numerous applications of ionic liquids. However, there remain discrepancies among the previous experimental and theoretical studies on the surface orientation and structures of room temperature ionic liquids(RTIL) systems. In this article, the orientation of 1-butyl-3-methylimidazolium([bmin]) cation at the air/liquid interface of a characteristic RTIL, 1-butyl-3-methylimidazolium hexafluorophosphate([bmim][PF6]), was investigated by the sum frequency generation vibrational spectroscopy(SFG-VS). Detailed polarization and experimental configuration analyses of the SFG-VS spectra showed the possibility of a small spectral splitting in the CH3 symmetric stretching region, which can be further attributed to the probable existence of multiple orientations for the interfacial [bmim] cations. In addition, the(N)–CH3 vibrations were absent, ruling out the prediction by several recent molecular dynamics simulations which state that portions of the [bmim] cations orient with a standing-up(N)–CH3 group at the ionic liquid surface. Hence, new realistic theoretical models have to be developed to reflect the complex nature of the ionic liquid surface. 相似文献
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