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1.
A new benzodithiophene (BDT)‐based polymer, poly(4,8‐bis(2‐ethylhexyloxy)benzo[1,2‐b:4,5‐b′]dithiophene vinylene) (PBDTV), was synthesized by Pd‐catalyzed Stille‐coupling method. The polymer is soluble in common organic solvents and possesses high thermal stability. PBDTV film shows a broad absorption band covering from 350 nm to 618 nm, strong photoluminescence peaked at 545 nm and high hole mobility of 4.84 × 10?3 cm2/Vs. Photovoltaic properties of PBDTV were studied by fabricating the polymer solar cells based on PBDTV as donor and PC70BM as acceptor. With the weight ratio of PBDTV: PC70BM of 1:4 and the active layer thickness of 65 nm, the power conversion efficiency of the device reached 2.63% with Voc = 0.71 V, Isc = 6.46 mA/cm2, and FF = 0.57 under the illumination of AM1.5, 100 mW/cm2. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1822–1829, 2010  相似文献   

2.
A soluble 4H‐cyclopenta[2,1‐b ;3,4‐b ′]dithiophene‐4‐one (CPDTO)‐based polymer (C6‐PCPDTO) has been synthesized from two monomers derived from nonalkylated CPDTO and didodecyl CPDTO (C12‐CPDTO). Proton NMR, thermal analysis, UV–vis absorption, cyclic voltammetry, and XRD are used to characterize the polymer in solution and film. The new polymer has an optical bandgap of 1.28 eV in film, and has strong interchain interaction in chloroform solutions. The polymer contains a significant amount of homocoupled segments. The regular segments and homocoupled CPDTO segments render the polymer highly aggregating in solution. The non‐planar homocoupled C12‐CPDTO segments prevent the polymer from forming regular π‐stacks, resulting in a low SCLC hole mobility (3.88 × 10?7 cm2V?1s?1). CV experiments show that C6‐PCPDTO is stable in its oxidized and reduced states. Solar cell devices were fabricated from C6‐PCPDTO2 :PC60BM blends of different weight ratios. High PC60BM loading (80% or greater) was required for the devices to show measurable efficiency, indicating that the limited π‐stacking of the polymer is not sufficient to cause effective phase separation. Further development of synthetic method is still needed to eliminate structural defects so that long‐range ordered pi‐stacking can be realized in the polymer for these applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 1077–1085  相似文献   

3.
Poly(3,4‐ethylenedioxypyrrole) (PEDOP)–Ag and PEDOP–Au nanocomposite films have been synthesized for the first time by electropolymerization of the conducting‐polymer precursor in a waterproof ionic liquid, 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, followed by Ag/Au nanoparticle incorporation. That the Ag/Au nanoparticles are not adventitious entities in the film is confirmed by a) X‐ray photoelectron spectroscopy, which provides evidence of Ag/Au–PEDOP interactions through chemical shifts of the Ag/Au core levels and new signals due to Ag–N(H) and Au–N(H) components, and b) electron microscopy, which reveals Au nanoparticles with a face‐centered‐cubic crystalline structure associated with the amorphous polymer. Spectroelectrochemistry of electrochromic devices based on PEDOP–Au show a large coloring efficiency (ηmax=270 cm2 C?1, λ=458 nm) in the visible region, for an orange/red to blue reversible transition, followed by a second, remarkably high ηmax of 490 cm2 C?1 (λ=1000 nm) in the near‐infrared region as compared to the much lower values achieved for the neat PEDOP analogue. Electrochemical impedance spectroscopy studies reveal that the metal nanoparticles lower charge‐transfer resistance and facilitate ion intercalation–deintercalation, which manifests in enhanced performance characteristics. In addition, significantly faster color–bleach kinetics (five times of that of neat PEDOP!) and a larger electrochemical ion insertion capacity unambiguously demonstrate the potential such conducting‐polymer nanocomposites have for smart window applications.  相似文献   

4.
The title compound, [Sr7(C7H3NO4)6(SO4)(H2O)6]n, has been synthesized by an ionothermal method using the ionic liquid 1‐ethyl‐3‐methylimidazolium ([Emim]Br) as solvent, and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR and single‐crystal X‐ray diffraction. The structure of the compound can be viewed as a three‐dimensional coordination polymer composed of Sr2+ cations, pyridine‐2,6‐dicarboxylate anions, sulfate anions and water molecules. The compound not only exhibits a three‐dimensional structure with a unique coordination mode of the sulfate anion, but also features the first example of a heptanuclear strontium(II) coordination polymer. The structure is further stabilized by O—H...O hydrogen bonds and π–π stacking interactions.  相似文献   

5.
3‐hexylthiophene was electropolymerized on a carbon nanotube (CNT)‐laden fluorine‐doped tin oxide substrate. Scanning electron microscopy and Raman spectroscopy revealed that the polymer was infused throughout the thickness of the 150‐nm thick CNT mat, resulting in a conducting composite film with a dense CNT network. The electropolymerized poly(3‐hexylthiophene) (e‐P3HT)/CNT composites exhibited photoluminescence intensity quenching by as much as 92% compared to the neat e‐P3HT, which provided evidence of charge transfer from the polymer phase to the CNT phase. Through‐film impedance and J‐V measurements of the composites gave a conductivity (σ) of 1.2 × 10?10 S cm?1 and zero‐field mobility (μ0) of 8.5 × 10?4 cm2 V?1 s?1, both of which were higher than those of neat e‐P3HT films (σ = 9.9 × 10?12 S cm?1, μ0 = 3 × 10?5 cm2 V?1 s?1). In electropolymerized samples, the thiophene rings were oriented in the (010) direction (thiophene rings parallel to substrate), which resulted in a broader optical absorbance than for spin coated samples, however, the lack of long‐range conjugation caused a blueshift in the absorbance maximum from 523 nm for unannealed regioregular P3HT (rr‐P3HT) to 470 nm for e‐P3HT. Raman spectroscopy revealed that π‐π stacking in e‐P3HT was comparable to that in rr‐P3HT and significantly higher than in regiorandom P3HT (ran‐P3HT) as shown by the principal Raman peak shift from 1444 to 1446 cm?1 for e‐P3HT and rr‐P3HT to 1473 cm?1 for ran‐P3HT. This work demonstrates that these polymer/CNT composites may have interesting properties for electro‐optical applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1269–1275, 2011  相似文献   

6.
In the title coordination polymer, [Pb(NCS)2(C12H12N2)], the coordination geometry about the PbII atom is a distorted octahedron, composed of two N atoms from bpe ligands [bpe is 1,2‐bis(4‐pyridyl)ethane], two other N atoms from NCS? groups and two neighbouring S atoms through short contacts. The trans‐bpe ligands act as bridges between two PbII centres resulting in the formation of a linear chain. The terminal S atoms of the NCS? ligands make short contacts with the PbII atom of neighbouring chains to form an infinite two‐dimensional polymeric structure.  相似文献   

7.
The title one‐dimensional chain polymer complex, [Mn(C6H4NO3)Cl(C6H5N)2]n, was isolated from the reaction of MnCl2 with 6‐oxo‐1,6‐dihydro­pyridine‐2‐carboxylic acid (HpicOH) in pyridine. The asymmetric unit contains one [Mn(HPicO)Cl(py)2] moiety (py is pyridine), with the (HpicO) ligand acting in a tridentate manner via the two carboxyl­ate O atoms and the pyridone O atom. The operation of inversion centres generates eight‐ and 14‐membered rings and, in conjunction with an a‐axis translation, leads to an infinite chain extending along [100]. The Mn⋯Mn separations in this chain are 5.1069 (6) and 7.1869 (6) Å. The MnII atom has a distorted octahedral coordination, with trans‐axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane. The conformation of the 14‐membered ring is stabilized by pairs of inversion‐related N—H⋯O hydrogen bonds.  相似文献   

8.
The novel complex di‐n‐butyltin(IV) 2‐oxo‐propionic acid (4‐pyridinecarbonyl) hydrazone, (n‐C4H9)2Sn‐[O2CC(CH3)=N‐N=C(‐O)C5N‐4] (H2O) has been synthesized and its structure has been determined by X‐ray diffraction analysis. The complex crystallizes in orthorhombic system with space group Pca21. Crystal data: a=2.7540(9) nm, b=0.9676(3) nm, c= 1.5750(5) nm, V=4.197(2) nm3, Dc= 1.444 g/cm3, Z=8. μ= 1.241 mm?1. F(000)= 1856, R1=0.0462 and wR2=0.1001. In the crystals of the title complex, the tin atom is in six‐coordination with a distorted octahedral geometry, three oxygen atoms [O(1), O(3) and O(4)] and one nitrogen atom N(1) forming the equatorial plane and C(10)‐Sn(1)‐C(14) being the axis. Two molecules form a dimer with weak interactions of Sn‐O bonding and hydrogen bonds.  相似文献   

9.
Two well‐defined alternating π‐conjugated polymers containing a soluble electroactive benzo[1,2‐b:4,5‐b′]difuran (BDF) chromophore, poly(BDF‐(9‐phenylcarbazole)) (PBDFC), and poly(BDF‐benzothiadiazole) (PBDFBTD) were synthesized via Sonogashira copolymerizations. Their optical, electrochemical, and field‐effect charge transport properties were characterized and compared with those of the corresponding homopolymer PBDF and random copolymers of the same overall composition. All these polymers cover broad optical absorption ranges from 250 to 750 nm with narrow optical band gaps of 1.78–2.35 eV. Both PBDF and PBDFBTD show ambipolar redox properties with HOMO levels of ?5.38 and ?5.09 eV, respectively. The field‐effect mobility of holes varies from 2.9 × 10?8 cm2 V?1 s?1 in PBDF to 1.0 × 10?5 cm2 V?1 s?1 in PBDFBTD. Bulk heterojunction solar cell devices were fabricated using the polymers as the electron donor and [6,6]‐phenyl‐C61‐butyric acid methyl ester as the electron acceptor, leading to power conversion efficiencies of 0.24–0.57% under air mass 1.5 illumination (100 mW cm?2). These results indicate that their band gaps, molecular electronic energy levels, charge mobilities, and molecular weights are readily tuned by copolymerizing the BDF core with different π‐conjugated units. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

10.
In the centrosymmetric title complex, [Ni(C7H7N4O3)2(C5H5N)2], the coordination geometry about the Ni2+ ion is octahedral, with two deprotonated 1‐methyl‐3‐(p‐nitro­phenyl)­triazenide 1‐oxide ions, viz. [O2N­C6H4­NNN(O)­CH3]?, acting as bidentate ligands (four‐electron donors). Two neutral pyridine (py) mol­ecules complete the coordination sphere in positions trans to each other. The triazenide 1‐oxide ligand is almost planar, the largest interplanar angle of 8.80 (12)° being between the phenyl ring of the p‐nitro­phenyl group and the plane defined by the N3O moiety. The Ni—Ntriazenide, Ni—O and Ni—Npy distances are 2.0794 (16), 2.0427 (13) and 2.1652 (18) Å, respectively.  相似文献   

11.
A new 3D hemidirected mixed‐ligand lead(II) coordination polymer with the ligand 1,2‐di(4‐pyridyl)ethane bpa) and the two metal coordinated anions nitrate and thiocyanate, [Pb2(bpa)2(SCN)3(NO3)]n ( 1 ), has been synthesized and characterized by CHN elemental analysis, IR‐, 1H‐ and 13C NMR spectroscopy. The single crystal X‐ray data of compound 1 show that the complex is a three‐dimensional coordination polymer with two different Pb atoms with stereoactive electron lone pairs and six‐ and five‐coordinate hemidirected geometries, respectively.  相似文献   

12.
The 2‐D heteronuclear coordination polymer {[Ag4Fe2(SCN)12(H2O)2] (inaH)2(H2O)2}n (1) (inaH is the abbreviation of protonated isonicotinic acid) with chemical formula C24Ag4Fe2N14O8S12 has been synthesized and characterized by single crystal X‐ray diffraction, elemental analysis and IR spectroscopy. The Ag2S2 rings connect two kinds of octahedral geometries of Fe(III) ions, [Fe(NCS)6]3– and Fe(H2O)2(NCS)4]? units with bridging thiocyanate ions leading to 2‐D [Ag4Fe2(SCN)12(H2O)22– anion framework. Four kinds of rings including the unprecedented thirty‐two membered Ag4Fe4(SCN)8 rings share comers or edges in the 2‐D anion layer structure. All thiocyanates coordinate to the metal ions according to the HSAB principle with N atoms binding to the Fe(III) ions and with S atoms binding to Ag(I) ions. Pronoated ina cations stabilize the layer structure as counter ions and hydrogen bonds were formed within the pronoated in a cations dimer and between the dimers and the lattice waters. Crystal data: Mr= 1560.44, triclinic, P1, a=0.76082(1) nm, b=0.9234 nm, c= 1.85611(4) nm, a= 103.0170(10)°, β=93.7780(10)°, y=97.4080(10)°, V= 1.25385(3) nm3, Z=1, μ(Mo Kα)=2.650 mm?1, Dc,=2.067 g · cm?3, F(000)=758, R1=0.0412. wR2=0.1003.  相似文献   

13.
The complex Eu(btfa)3 (phen) (btfa=4,4,4‐trifluoro‐1‐phenyl‐1, 3‐butanedione, phen = 1,10‐phenanthroline) has been prepared and characterized by elemental analysis, IR and UV spectroscopies. The crystal and molecular structures of the complex have been determined by X‐ray diffraction analysis. It belongs to the monoclinic crystal system, space group P21/c with a = 0.9700(2) nm, b = 3.7450(5) nm, c = 1.0917(3) nm, β = 92.51(2)°, V = 3.962(1) nm5, Z = 4, Dc = 1.639 g/cm3, μ = 1.676 mm?1, F(000) = 1936, R1, = 0.0388, wR2 = 0.0775. Structure analysis shows that the europium(III) ion is coordinated to six oxygen atoms of β‐diketonate anions and two nitrogen atoms of phenanthroline molecule. The coordination polyhedron is an approximate square antiprism.  相似文献   

14.
New amorphous semiconducting copolymers, poly(9,9‐dialkylfluorene)‐alt‐(3‐dodecylthienyl‐divinylbenzene‐3‐dodecylthienyl) derivatives (PEFTVB and POFTVB), were designed, synthesized, and characterized. The structure of copolymers was confirmed by H NMR, IR, and elemental analysis. The copolymers showed very good solubility in organic solvents and high thermal stability with high Tg of 178–185 °C. The weight average molecular weight was found to be 107,900 with polydispersity of 3.14 for PEFTVB and 76,700 with that of 3.31 for POFTVB. UV–vis absorption studies showed the maximum absorption at 428 nm (in solution) and 435 nm (in film) for PEFTVB and at 430 nm (in solution) and 436 nm (in film) for POFTVB. Photoluminescence studies showed the emission at 498 nm (in solution) and 557 nm (in film) for PEFTVB and at 498 nm (in solution) and 536 nm (in film) for POFTVB. The solution‐processed thin‐film transistors showed the carrier mobility of 2 × 10?4 cm2 V?1 s?1 for PEFTVB‐based devices and 2 × 10?5 cm2 V?1 s?1 for POFTVB‐based devices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3942–3949, 2010  相似文献   

15.
Preparation and Spectroscopic Characterization of the Pure Bondisomers [OsCl5(NCS)]2? and [OsCl5(SCN)]2? The oxidation of [OsCl5I]2? with (SCN)2 in CH2Cl2 yields the bondisomers [OsCl5(NCS)]2? and [OsCl5(SCN)]2?, which are isolated as pure compounds by ion exchange chromatography on DEAE-Cellulose. Only the salts of the N-isomer show significant shifts in the vibrational and electronic spectra caused by polarization of the terminal S depending on the size of the cations and the polarity of the solvents. In the IR and Raman spectra νCN(S), νCS(N) and δNCS are found at higher wave numbers than νCN(N), νCS(S) and δSCN. In the optical spectrum of the red [OsCl5(SCN)]2? the charge-transfer S→Os is nearly constant at 538 nm, but the N→Os transition of the yellow to violet coloured N-isomer shifts from 480 nm in organic solvents or in presence of large alkylammonium cations to 516 nm in aqueous solution and to 544 nm in the solid Cs-salt. The optical electronegativities are calculated to χopt(–SCN) = 2.6 and χopt(–NCS) = 2.6–2.8. According to spinorbit coupling and to lowered symmetry (C4v) the splitted intraconfigurational transitions are observed at 10 K as weak peaks in the regions 600, 1000 and 2000 nm. The O? O transitions are calculated from the vibrational fine structure. The lowest level of both isomers is confirmed by peaks in the electronic raman spectra. With the parameters ζ(OsIV) = 3200 cm?1 and B(? SCN) = 316 cm?1 or B(? NCS) = 288 cm?1 there is a good fit of calculated and experimental data, resulting in the nephelauxetic series: F? > CI? > SCN? > Br? > NCS? > I?.  相似文献   

16.
The asymmetric unit of the title two‐dimensional coordination polymer, {[Cd(C14H8O4)(C14H14N4)]·0.15H2O}n, is composed of one CdII cation, one biphenyl‐2,4′‐dicarboxylate (bpdc) anion, one 1,4‐bis(imidazol‐1‐ylmethyl)benzene (bix) ligand and 0.15 solvent water molecules. The coordination environment of the CdII cation is defined by four carboxylate O atoms from two different bpdc anions in a chelating mode and two N atoms from two distinct bix ligands, constructing a distorted trigonal prism polyhedron. Two inversion‐related CdII cations are bridged together by two positionally disordered bpdc anions, forming a 22‐membered ring with a Cd...Cd distance of 9.1966 (9) Å. These rings are then further linked by two bix ligands, extending into a two‐dimensional layer along (102) with 63 topology.  相似文献   

17.
As a novel ultraviolet (UV) absorbent with excellent performance in UVA section (320 ~ 400 nm), 2‐{2‐hydroxy‐4‐[(octyloxycarbonyl)ethylideneoxy]phenyl}‐4,6‐Bis(4‐biphenylyl)‐1,3,5‐triazine (CGL‐479) was synthesized in a simple method with a total yield of 45.3% in four steps. Its outstanding UV absorption capability (λmax = 326 nm, εmax = 4.15 × 104 L?mol?1?cm?1), high thermostability [T5 (the temperature of losing 5% in weight) = 385 °C], and compatibility with polymer materials make it a potential substitute of the traditional UV absorbents.  相似文献   

18.
A series of new phenothiazine‐based donor–acceptor copolymers, P1 and P2, were synthesized via a Suzuki coupling reaction. The weight‐averaged molecular weights (Mw) of P1 and P2 were found to be 16,700 and 16,100, with polydispersity indices of 1.74 and 1.39, respectively. The UV–visible absorption spectra of the polymer thin films contained three strong absorption bands in the ranges 318–320 nm, 430–436 nm, and 527–568 nm. The absorption peaks at 320 and 430 nm originated mainly from the phenothiazine‐based monomer units, and the longer wavelength absorption band at 527–568 nm was attributed to the increased effective conjugation length of the polymer backbones. Solution‐processed field‐effect transistors fabricated with these polymers exhibited p‐type organic thin film transistor characteristics. The field‐effect mobilities of P1 and P2 were measured to be 1.0 × 10?4 and 7.5 × 10?5 cm2 V?1 s?1, respectively, with on/off ratios in the order of 104 for all polymers. A photovoltaic device in which a P2/PC71BM (1/3) blend film was used as the active layer exhibited an open‐circuit voltage (VOC) of 0.70 V, a short‐circuit current (JSC) of 6.79 mA cm(2, a fill factor of 0.39, and a power conversion efficiency of 1.86% under AM 1.5 G (100 mW cm?2) illumination. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

19.
Zn(meadtc)2(2,2′‐bipy) is a ZnS3N2 chromophore with a distorted square pyramidal geometry. The IR band at 1002 cm?1 and the bond valence sum value of 1.98 confirmed the monodentate dithiocarbamate in coordination. The non‐bonding Zn–S distance is 5.004(3) Å. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

20.
The synthesis of coordination polymers or metal–organic frameworks (MOFs) has attracted considerable interest owing to the interesting structures and potential applications of these compounds. It is still a challenge to predict the exact structures and compositions of the final products. A new one‐dimensional coordination polymer, catena‐poly[[[bis{1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole‐κN3}zinc(II)]‐μ‐hexane‐1,6‐dicarboxylato‐κ4O1,O1′:O6,O6′] monohydrate], {[Zn(C6H8O4)(C9H8N6)2]·H2O}n, has been synthesized by the reaction of Zn(Ac)2 (Ac is acetate) with 1‐[(1H‐benzimidazol‐2‐yl)methyl]‐1H‐tetrazole (bimt) and adipic acid (H2adi) at room temperature. In the polymer, each ZnII ion exhibits an irregular octahedral ZnN2O4 coordination geometry and is coordinated by two N atoms from two symmetry‐related bimt ligands and four O atoms from two symmetry‐related dianionic adipate ligands. ZnII ions are connected by adipate ligands into a one‐dimensional chain which runs parallel to the c axis. The bimt ligands coordinate to the ZnII ions in a monodentate mode on both sides of the main chain. In the crystal, the one‐dimensional chains are further connected through N—H…O hydrogen bonds, leading to a three‐dimensional supramolecular architecture. In addition, the title polymer exhibits fluorescence, with emissions at 334 and 350 nm in the solid state at room temperature.  相似文献   

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