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121.
Polymer electron acceptors are the key materials in all-polymer solar cells(all-PSCs).In this review,we focused on introducing the principle of boron-nitrogen coordination bond(B←N),and summarizing our recent research on polymer electron acceptors containing B←N unit for efficient all-PSC devices.Two approaches have been reported to design polymer electron acceptors using B←N unit.One is to replace a C-C unit by a B←N unit in conjugated polymers to transform a polymer electron donor to a polymer electron acceptor.The other approach is to construct novel electron-deficient building block based on B←N unit for polymer electron acceptors.The polymer electron acceptors containing B←N unit showed tunable lowest unoccupied molecular orbital(LUMO) energy levels and exhibited excellent all-PSC device performance with power conversion efficiency of exceeding6%.These results indicate that organic boron chemistry is a new toolbox to develop functional polymer materials for optoelectronic device applications. 相似文献
122.
123.
Li-Guo YangCheng-Chen Zhu Dao-Peng Zhang Da-Cheng LiDa-Qi Wang Jian-Min Dou 《Polyhedron》2011,30(9):1469-1477
Five new carborane dicyclohexylphosphine complexes, [Ag2(μ-I)2{1,2-(P Cy2)2-1,2-C2B10H10}2] (1), [Ag2(SCN)2{1,2-(PCy2)2-1,2-C2B10H10}2]n·CH2Cl2 (2), [Ag(ClO4){1,2-(PCy2)2-1,2-C2B10H10}]·CH2Cl2 (3), [Ag2(μ-NO3)2{1,2-(PCy2)2-1,2-C2B10H10}2]·CH2Cl2 (4) and [Ag(SC6H4COOH){1,2-(PCy2)2-1,2-C2B10H10}2]·CH2Cl2 (5), have been synthesized by the reactions of 1,2-bis(dicyclohexylphosphino)-1,2-dicarba-closo-dodecaborane with AgX (X = I, SCN, ClO4, NO3 and SC6H4COOH) in CH2Cl2. The structures of the five complexes were characterized by elemental analysis, FT-IR, 1H, 13C, 11B and 31P NMR spectroscopy. X-ray structure analysis revealed that the structures of the complexes can be classified into three types. Complexes 1 and 4 are di-μ-X-bridged structures and complexes 3 and 5 are mononuclear structures, while complex 2 is a chain-like polymer. Complexes 1 and 2 form 2D supramolecular networks and complexes 3, 4 and 5 form 1D chains via C-H?H-B dihydrogen bonding interactions. 相似文献
124.
Houjian Gong Guiying Xu Teng Liu Jinyu Pang Wenling Dou Xia Xin 《Colloid and polymer science》2011,289(8):933-942
The block polyethers with different structure and composition were synthesized by anionic polymerization and used to disperse single-walled carbon nanotubes (SWNTs). The block polyethers with the structure of branch or benzene ring had better dispersion ability than the commercial Pluronic block polyethers (L64 and F127). In order to compare the parameters, dispersion limit and efficiency of polyethers for SWNTs were defined. UV?Cvis?Cnear infrared absorbance spectra showed that eight-branch polyether AE82 had much larger dispersion limit and efficiency than five-branch AE52. BPE containing benzene rings in the molecule had a slightly lower dispersion limit but larger dispersion efficiency than AE82. The defect density of SWNTs dispersed in polyether aqueous solutions was investigated by Raman spectroscopy. The polyethers AE83 and BEP with the structure of poly(ethylene oxide)?Cpoly(propylene oxide) dispersed less defective SWNTs than AE82 and BPE, indicating that the variation of polyether structure and composition could influence the defect density of SWNTs besides dispersion limit and efficiency. 相似文献
125.
A series of phosphate or phosphate-acetate hybrid modified EGCG or EGCG G ring deoxy analogs were synthesized by a convenient semi-synthesis strategy from the abundant natural compound EGCG. 相似文献
126.
Molecule-substrate interaction channels of metal-phthalocyanines (MPcs, including NiPc, CuPc, ZnPc, FePc, and CoPc) on graphene on Ni(111) were investigated by employing high-resolution electron energy loss spectroscopy (HREELS). Except the expected IR-active modes, some Raman-active modes were also observed in all of MPcs, which are considered in this study. From the origination of the Raman-active features, it was deduced that MPcs are coupled with the substrate mainly through their central metal atom. The Raman-active modes appear as symmetric peaks in the HREELS in the case of MPcs with Ni, Cu, and Zn, whereas they are asymmetric and appear as a Fano line shape in the case of MPcs with Fe and Co. This spectroscopic difference indicates that the molecule-substrate coupling is completely different in the two cases mentioned above. The molecule-substrate interaction strength is considerably weak and comparable with the π-π interaction between molecules in the case of MPcs with Ni, Cu, and Zn, whereas it is much stronger in the case of MPcs with Fe and Co. From the HREELS observations, it can be suggested that the whole molecule can be effectively decoupled from the underneath Ni(111) by inserting a single layer of graphene between them in the case of MPcs with Ni, Cu, and Zn, whereas only benzene rings can be completely decoupled in the case of MPcs with Fe and Co. 相似文献
127.
128.
An efficient and convenient method for the preparation of cis-bispyrimidodiazepinone derivatives has been described. A variety of substrates can participate in the process with good yields, making this methodology suitable for library synthesis in drug discovery efforts. The mechanistic course of the reaction suggests the involvement of reduction, coupling which determine the products' configuration and cyclization by one-pot. 相似文献
129.
Hu X Dou W Xu C Tang X Zheng J Liu W 《Dalton transactions (Cambridge, England : 2003)》2011,40(13):3412-3418
A bi-phosphonate ligand tetraethyl-(2,3,5,6-tetramethyl-1,4-phenylene) bis(methylene)diphosphonate has been designed and synthesized. The bi-phosphonate as a bridging ligand reacts with lanthanide nitrates forming four different types of 1D coordination complexes: ribbon polymer (type I), semi-ribbon polymer (type II), zigzag polymer (type III), and dinuclear-triligand short chain (type IV), which changed according to the decrease of the radius of the lanthanide. They have been characterized by IR spectroscopy, elemental analysis, and X-ray diffraction spectroscopy. The photophysical properties of Sm(3+), Eu(3+), Tb(3+) and Dy(3+) complexes at room temperature were also investigated. They exhibit strong fluorescence by excitation of the Ln(3+) ion absorption bands and the quantum yield values of Eu(3+) and Tb(3+) complexes are no less than 20%. 相似文献
130.
Feng D Lv Y Wu Z Dou Y Han L Sun Z Xia Y Zheng G Zhao D 《Journal of the American Chemical Society》2011,133(38):15148-15156
We report for the first time the synthesis of free-standing mesoporous carbon films with highly ordered pore architecture by a simple coating-etching approach, which have an intact morphology with variable sizes as large as several square centimeters and a controllable thickness of 90 nm to ~3 μm. The mesoporous carbon films were first synthesized by coating a resol precursors/Pluronic copolymer solution on a preoxidized silicon wafer and forming highly ordered polymeric mesostructures based on organic-organic self-assembly, followed by carbonizing at 600 °C and finally etching of the native oxide layer between the carbon film and the silicon substrate. The mesostructure of this free-standing carbon film is confirmed to be an ordered face-centered orthorhombic Fmmm structure, distorted from the (110) oriented body-centered cubic Im3?m symmetry. The mesoporosity of the carbon films has been evaluated by nitrogen sorption, which shows a high specific BET surface area of 700 m(2)/g and large uniform mesopores of ~4.3 nm. Both mesostructures and pore sizes can be tuned by changing the block copolymer templates or the ratio of resol to template. These free-standing mesoporous carbon films with cracking-free uniform morphology can be transferred or bent on different surfaces, especially with the aid of the soft polymer layer transfer technique, thus allowing for a variety of potential applications in electrochemistry and biomolecule separation. As a proof of concept, an electrochemical supercapacitor device directly made by the mesoporous carbon thin films shows a capacitance of 136 F/g at 0.5 A/g. Moreover, a nanofilter based on the carbon films has shown an excellent size-selective filtration of cytochrome c and bovine serum albumin. 相似文献