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1.
Compact molecular packing with short π-π stacking and large π-overlap in organic semiconductors is desirable for efficient charge transport and high carrier mobility.Thus charge transport anisotropy along different directions is commonly observed in organic semiconductors.Interestingly,in this article,we found that comparable charge transport property were achieved based on the single crystals of a bis-fused tetrathiafulvalene derivative(EM-TTP) compound along two interaction directions,that is,the multiple strong S…S intermolecular interactions and the π-π stacking direction,with the measured electrical conductivity and hole mobility of 0.4 S cm~(-1),0.94 cm~2 V~(-1) s~(-1) and 0.2 S cm~(-1),0.65 cm2 V~(-1) s~(-1),respectively.This finding provides us a new molecular design concept for developing novel organic semiconductors with isotropic charge transport property through the synergistic effect of multiple intermolecular interactions(such as S…S interactions) and π-π stacking.  相似文献   

2.
V2O3(OH)4(g), Proof of Existence, Thermochemical Characterization, and Chemical Vapor Transport Calculations for V2O5(s) in the Presence of Water By use of the Knudsen-cell mass spectrometry the existence of V2O3(OH)4(g) is shown. For the molecules V2O3(OH)4(g), V4O10(g), and V4O8(g) thermodynamic properties were calculated by known Literatur data. The influence of V2O3(OH)4(g) for chemical vapor transport reactions of V2O5(s) with water ist discussed. ΔBH°(V2O3(OH)4(g), 298) = –1920 kJ · mol–1 and S°(V2O3(OH)4(g), 298) = 557 J · K–1 · mol–1, ΔBH°(V4O10(g), 298) = –2865,6 kJ · mol–1 and S°(V4O10(g), 298) = 323.7 J · K–1 · mol–1, ΔBH°(V4O8(g), 298) = –2465 kJ · mol–1 and S°(V4O8(g), 298) = 360 J · K–1 · mol–1.  相似文献   

3.
The development of selenophene‐flanked DPP (SeDPP) based copolymers, especially for the ambipolar ones, lags behind other aromatic group flanked DPP‐based polymers. Herein, we report two new ambipolar SeDPP‐based conjugated polymers. One is the alternating polymer PSeDPPFT with normal SeDPP and 3,4‐difluorothiophene units. The other is PSeFDFT , in which the electron acceptor unit is replaced by a new SeDPP derivative, referred as to half‐fused SeDPP. The more planar structure of half‐fused SeDPP endows the backbone of PSeFDFT with good rigidity and planarity. Both polymers exhibit ambipolar transporting properties in air. The PSeFDFT based field‐effect transistors (FETs) display higher and more balanced ambipolar properties with μhave of 0.27 cm2·V–1·s–1, μeave of 0.18 cm2·V–1·s–1, and μhave/μeave of 1.5 than those of PSeDPPFT (μhave = 0.11 cm2·V–1·s–1, μeave = 0.042 cm2·V–1·s–1, and μh/μe = 2.6). This is attributed to the more planar structure, lower LUMO level, higher HOMO level, and better interchain packing orientations of PSeFDFT by comparing with PSeDPPFT . Therefore, a new molecular design strategy to modulate the hole and electron transporting properties is proposed for conjugated D‐A polymers.  相似文献   

4.
The effect of Er3+ doping (1%) on the structural, optical and photocatalytic properties of In2O3 thin films deposited on quartz substrates by spin coating was investigated. The In2O3:1% Er3+ films, annealed in the temperature range 800–1000 °C, were characterized by X-ray diffraction, scanning electron microscopy (SEM), atomic force microscopy, UV–Vis spectroscopy, ellipsometry and photoluminescence (PL). The films are polycrystalline with a cubic structure and the lattice parameter increases with the incorporation of Er3+ owing to its larger radius. The SEM images of the film show a granular morphology with large grains (~ 200 nm). The doped In2O3 film exhibits less transparency than In2O3 in the UV–visible region with band gaps of 3.42 and 3.60 eV, respectively. PL shows strong lines at 548 and 567 nm, assigned to Er3+ under direct excitation at 532 nm. The energy diagram of the junction In2O3:1% Er3+/Na2SO4 (0.1 M) solution plotted from physical and photoelectrochemical characterizations shows the feasibility of the films for Rhodamine B (RhB) degradation under solar light. The conduction band at 2.22 V deriving from the In3+:5s orbital is suitably positioned with respect to the O2/O 2 · level (~ 1.40 VSCE), leading to oxidation of 32% of 10 ppm RhB within 40 min of solar irradiation.  相似文献   

5.
Multilayered heterostructures comprising of In2O3, SnO2, and Al2O3 were studied for their application in thin-film transistors (TFT). The compositional influence of tin oxide on the properties of the thin-film, as well as on the TFT characteristics is investigated. The heterostructures are fabricated by atomic layer deposition (ALD) at 200 °C, employing trimethylindium (TMI), tetrakis(dimethylamino)tin (TDMASn), trimethylaluminum (TMA), and water as precursors. After post-deposition annealing at 400 °C the thin-films are found to be amorphous, however, they show a discrete layer structure of the individual oxides of uniform film thickness and high optical transparency in the visible region. Incorporation of only two monolayers of Al2O3 in the active semiconducting layer the formation of oxygen vacancies can be effectively suppressed, resulting in an improved semiconducting and switching behavior. The heterostacks comprising of In2O3/SnO2/Al2O3 are incorporated into TFT devices, exhibiting a saturation field-effect mobility (μsat) of 2.0 cm2 ⋅ V−1 s−1, a threshold-voltage (Vth) of 8.6 V, a high current on/off ratio (IOn/IOff) of 1.0×107, and a subthreshold swing (SS) of 485 mV ⋅ dec−1. The stability of the TFT under illumination is also altered to a significant extent. A change in the transfer characteristic towards conductive behavior is evident when illuminated with light of an energy of 3.1 eV (400 nm).  相似文献   

6.
An inorganic–organic hybrid compound, (H2bpy)3[AsIIIAs2 VMo15 VIMo3 VO62]·3H2O (bpy: 4,4′-bipyridine) (1) has been synthesized under hydrothermal conditions and characterized by elemental analysis, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction, IR spectrum, UV–Vis spectrum, thermogravimetric analysis and single-crystal X-ray diffraction. The crystallographic analysis reveals that compound 1 is composed of a Wells–Dawson polyoxoanion [As2 VMo15 VIMo3 VO62]9? with the mixed valence of MoV,VI, which acts as a tetradentate ligand coordinating with the AsIII cation to form the mixed valence AsIII,V containing arsenomolybdate with the single cap structure in a chelate coordination mode. In the solid state, compound 1 shows a 3D supramolecular structure through hydrogen-bonding interactions (C–H···O, N–H···O, N–H···N). In addition, compound 1 exhibits reversible multi-electron redox processes and effective electrocatalytic activities towards the reduction of H2O2, NaNO2 and KBrO3. Moreover, compound 1 is used as a reducing agent of the graphene oxide to prepare graphene by a green chemistry type one-step synthesis method, which is characterized by XPS, Raman spectroscopy, PXRD, IR, scanning electron microscopy and transmission electron microscopy.  相似文献   

7.
Of the four reduced indium bromides, InBr, In2Br3, InBr2, and In4Br7, synthesis, crystal growth and structure determination of the first three is reported. InBr (orthorhombic), Cmcm, Z = 4, a = 446.6(1), b = 1236.8(2), c = 473.9(1) pm, Vm = 39.42(1) cm3 mol?1) crystallizes with the TlI-type structure. In2Br3 (orthorhombic, Pnma, Z = 16, a = 1300.6(5), b = 1649.8(5), c = 1289.7(9) pm, Vm = 104.16(9) cm3 mol ?1), isotypic with Ga2Br3, is according to In2[In2Br6] a mixed-valence InI–InII-bromid with eclipsed [In2Br6]2? groups with d(In–In) = 268.8 and 271.6 pm, respectively. InBr2(?In[InBr4]) is a mixed-valence InI? InIII bromide with the GaCl2-type structure (orthorhombic, Pnna, Z = 8, a = 798.6(2), b = 1038.5(2), c = 1042.5(5) pm, Vm = 65.09(4) cm3 mol?1).  相似文献   

8.
The effects of the addition of silica nanoparticles (SNPs) on wettability of regioregular poly(3‐hexylthiophene) (P3HT) organic semiconductor solutions on hydrophobic substrates and the carrier mobility in organic field‐effect transistors (OFETs) made of these films are investigated. The dewetting of films made from P3HT solutions on hydrophobic substrates modified with octadecyltrichlorosilane (ODTS) is markedly suppressed after the addition of SNPs with phenyl surfactants. This enables us to fabricate continuous P3HT/SNPs films with high crystallinity by the conventional spin‐coating technique, leading to higher mobility compared with P3HT FETs fabricated on non‐modified substrates. Moreover, the addition of SNPs with larger diameters compensates for the degradation of mobility associated with the increase in the concentration of SNPs. Solution‐processed P3HT/SNPs FETs on ODTS‐modified substrates exhibit a field‐effect mobility of 1.3 × 10?2 cm2 V?1 s?1, which is almost comparable to that of P3HT FETs without SNPs (2.1 × 10?2 cm2 V?1 s?1). © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 509–516  相似文献   

9.
采用旋涂法用浓度分别为0.05,0.10和0.25 mol·L-1的氧化锌前躯体溶液制备了氧化锌薄膜,并且制备了基于氧化锌多层膜的顶栅极晶体管器件,其中以利用光刻工艺刻蚀的氧化铟锡为源漏电极。通过原子力显微镜(AFM)和X-射线衍射(XRD)分别表征了薄膜的形貌以及结晶情况,并且讨论了前躯体的浓度顺序对氧化锌多层膜的影响。按照浓度从大到小的顺序依次旋涂前躯体溶液制备的氧化锌薄膜表现出了较高的载流子迁移率(7.1×10-3 cm2·V-1·s-1),而按照浓度从小到大的顺序依次旋涂前躯体溶液制备的氧化锌薄膜的载流子迁移率为5.2×10-3 cm2·V-1·s-1。文中通过对两种多层薄膜的形貌和结晶性能的分析表明影响顶栅极薄膜晶体管性能的主要因素是薄膜的粗糙度。平整的薄膜有利于形成较好的半导体层/绝缘层接触界面,从而有利于提高器件的载流子迁移率。  相似文献   

10.
Density functional theory (DFT) calculations were carried out to investigate the organic field effect transistor (OFET) performance of the symmetrical metal-free tetrakis (1,2,5-thiadiazole) porphyrazine (S4)PzH2 and tetrakis (1,4-diamyloxybenzene) (A4)PzH2 as well as the low-symmetry metal-free porphyrazine with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene groups in the ratio 2:2 (cis) and 1:3, that is, (cis-S2A2)PzH2 and (SA3)PzH2, (S = 1,2,5-thiadiazole ring, A = annulated 1,4-diamyloxy-benzene ring, Pz = porphyrazine) in terms of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy, ionization energy (IE), electron affinity (EA), and their reorganization energy (λ) during the charge-transport process. On the basis of Marcus electron transfer theory, electronic couplings (V) and field effect transistor (FET) properties for the four compounds with known crystal structure have been calculated. The electron transfer mobility (μ) is revealed to be 0.056 cm2·V−1·s−1 for (S4)PzH2. The hole transfer mobility (μ+) is 0.075, 0.098, and 8.20 cm2·V−1·s−1 for (cis-S2A2)PzH2, (SA3)PzH2, and (A4)PzH2, respectively. The present work represents the theoretical effort towards understanding the OFET properties of symmetrical and unsymmetrical porphyrazine derivatives with annulated 1,2,5-thiadiazole and 1,4-diamyloxybenzene. Supported by the National Natural Science Foundation of China (Grant No. 50673051) and Beijing Municipal Commission of Edueation  相似文献   

11.
Mesomorphous butterfly-like shape molecules based on benzodithiophene, benzodithiophene-4,8-dione and cyclopentadithiophen-4-one core moieties were efficiently synthesized by the Suzuki-Miyaura coupling and Scholl oxidative cyclo-dehydrogenation reactions’ tandem. Most of the butterfly molecules spontaneously self-organize into columnar hexagonal mesophase. The electron-deficient systems possess strong solvent-gelling ability but are not luminescent, whereas the electron-rich terms do not form gels but strongly emit light between 400 and 600 nm. The charge carrier mobility was also measured by time-of-flight transient photocurrent technique in the mesophases for some of the compounds. They display hole-transport performances with positive charge mobility in the 10−3 cm−2 V−1 s−1 range, consistent with the high degree of ordering and stability of the columnar superstructures. In particular, the mesogen with a benzodithiophen-4,8-dione core shows ambipolar charge carrier transport with both high electron (μe=6.6×10−3 cm−2 V−1 s−1) and hole (μh=4.5×10−3 cm−2 V−1 s−1) mobility values.  相似文献   

12.
Two new inorganic–organic vanadate hybrid compounds [Mn(Hbbi)2(V4O12)] ( 1 ) and [Cd(Hbbi)2(V4O12)] ( 2 ) (bbi = 1,1’‐(1,4‐butanediyl)bis(imidazole)) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG and single‐crystal X‐ray diffraction. The two compounds crystallize in monoclinic system, P21/c space group with a = 8.556(5) Å, b = 10.761(5) Å, c = 16.917(5) Å, β = 93.032(5) o, V = 1555.4(12) Å3, Z = 2, R = 0.0390 for 1 and a = 8.657(5) Å, b = 10.743 (5) Å, c = 16.864 (5) Å, β = 93.81(5)o, V = 1564.9 (12) Å3, Z = 2, R = 0.0717 for 2 . Single‐crystal X‐ray diffraction analysis reveals that the two compounds are isostructural and both consist of one‐dimensional (1D) chains, which are constructed from vanadate anion clusters and [M(Hbbi)2]4+ cation groups [M = MnII ( 1 ), CdII ( 2 )]. Moreover, the polymeric chains are ultimately packed into a three‐dimensional (3D) supramolecular framework through C–H ··· O and N–H ··· O hydrogen bonding interactions.  相似文献   

13.
Donor–acceptor block copolymers (BCP), incorporating poly(3‐hexylthiophene) (P3HT), and a polystyrene copolymer with pendant fullerenes (PPCBM) provide desired stable nanostructures, but mostly do not exhibit balanced charge carrier mobilities. This work presents an elegant approach to match hole and electron transport in BCP by blending with molecular PCBM without causing any macrophase separation. An insufficient electron mobility of PPCBM can be widely compensated by adding PCBM which is monitored by the space‐charge limited current method. Using X‐ray diffraction, atomic force microscopy, and differential scanning calorimetry, we verify the large miscibility of the PPCBM:PCBM blend up to 60 wt % PCBM load forming an amorphous, molecularly mixed fullerene phase without crystallization. Thus, blending BCP with PCBM substantially enhances charge transport achieving an electron mobility of μe=(3.2 ± 1.7) × 10?4 cm2V?1s?1 and hole mobility of μh=(1.8 ± 0.6) × 10?3 cm2V?1s?1 in organic field‐effect transistors (OFET). The BCP:PCBM blend provides a similarly high ambipolar charge transport compared to the established P3HT:PCBM system, but with the advantage of an exceptionally stable morphology even for prolonged thermal annealing. This work demonstrates the feasibility of high charge transport and stable morphology simultaneously in a donor–acceptor BCP by a blend approach. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1125–1136  相似文献   

14.
A simple azulene‐containing squaraine dye ( AzUSQ ) showing bandgap of 1.38 eV and hole mobility up to 1.25×10?4 cm2 V?1 s?1 was synthesized. With its low bandgap, an organic photovoltaic (OPV) device based on it has been made that exhibits an impressive open‐circuit voltages (Voc) of 0.80 V. Hence, azulene might be a promising structural unit to construct OPV materials with simultaneous low bandgap, high hole mobility and high Voc.  相似文献   

15.
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   

16.
A fused-ring electron acceptor IDT-2BR1 based on indacenodithiophene core with hexyl side-chains flanked by benzothiadiazole rhodanine was designed and synthesized.In comparison with its counterpart with hexylphenyl side-chains(IDT-2BR),IDT-2BR1exhibits higher highest occupied molecular orbital(HOMO)energy but similar lowest unoccupied molecular orbital(LUMO)energy(IDT-2BR1:HOMO=-5.37eV,LUMO=-3.67eV;IDT-2BR:HOMO=-5.52eV,LUMO=-3.69eV),red-shifted absorption and narrower bandgap.IDT-2BR1 has higher electron mobility(2.2×10~(-3)cm~2 V~(-1)s~(-1))than IDT-2BR(3.4×10~(-4)cm~2 V~(-1)s~(-1))due to the reduced steric hindrance and ordered molecular packing.Fullerene-free organic solar cells based on PTB7-Th:IDT-2BRl yield power conversion efficiencies up to 8.7%,higher than that of PTB7-Th:IDT-2BR(7.7%),with a high open circuit voltage of0.95 V and good device stability.  相似文献   

17.
Cavity ring‐down UV absorption spectroscopy was used to study the kinetics of the recombination reaction of FCO radicals and the reactions with O2 and NO in 4.0–15.5 Torr total pressure of N2 diluent at 295 K. k(FCO + FCO) is (1.8 ± 0.3) × 10−11 cm3 molecule−1 s−1. The pressure dependence of the reactions with O2 and NO in air at 295 K is described using a broadening factor of Fc = 0.6 and the following low (k0) and high (k) pressure limit rate constants: k0(FCO + O2) = (8.6 ± 0.4) × 10−31 cm6 molecule−1 s−1, k(FCO + O2) = (1.2 ± 0.2) × 10−12 cm3 molecule−1 s−1, k0(FCO + NO) = (2.4 ± 0.2) × 10−30 cm6 molecule−1 s−1, and k (FCO + NO) = (1.0 ± 0.2) × 10−12 cm3 molecule−1 s−1. The uncertainties are two standard deviations. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 130–135, 2001  相似文献   

18.
This work reports development of yttrium doped copper oxide (Y−CuO) as a new hole transport material with supplemented optoelectronic character. The pure and Y-doped CuO thin films are developed through a solid-state method at 200 °C and recognized as high performance p-channel inorganic thin-film transistors (TFTs). CuO is formed by oxidative decomposition of copper acetylacetonate, yielding 100 nm thick and conductive (40.9 S cm−1) compact films with a band gap of 2.47 eV and charge carrier density of ∼1.44×1019 cm−3. Yttrium doping generates denser films, Cu2Y2O5 phase in the lattice, with a wide band gap of 2.63 eV. The electrical conductivity increases nine-fold on 2 % Y addition to CuO, and the carrier density increases to 2.97×1021 cm−3, the highest reported so far. The TFT devices perform remarkably with high field-effect mobility (μsat) of 3.45 cm2 V−1 s−1 and 5.3 cm2 V−1 s−1, and considerably high current-on/off ratios of 0.11×104 and 9.21×104, for CuO and Y−CuO films, respectively (at −1 V operating voltage). A very small width hysteresis, 0.01 V for CuO and 1.92 V for 1 % Y−CuO, depict good bias stability. Both the devices work in enhancement mode with stable output characteristics for multiple forward sweeps (5 to −60 V) at −1Vg.  相似文献   

19.
Four inorganic–organic hybrid compounds, [M2(CuL)4(V4O12)]·2H2O (M?=?Co (1), Mn (2)), [Mn2(NiL)4(V4O12)]·2H2O (3), and [Zn2(CuL)4(V4O12)]·2CH3OH·2H2O (4) (M′L, H2L?=?2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien), have been synthesized and characterized by elemental analysis, IR, UV, fluorescence spectra, and X-ray diffraction analysis. Single-crystal X-ray analysis reveal that both [V4O12]4? and M2V4 adapt a chair-like configuration in four structures. The cyclovanadate group [V4O12]4? is a tetradentate bridging ligand linking two [M(M′L)2]2+ fragments, producing centroantisymmetric heterometallic hexanuclear [M2M′4] complexes. The variable-temperature magnetic susceptibility measurements (2–300?K) of 1 and 2 show weak antiferromagnetic interactions.  相似文献   

20.
Inorganic–organic hybrid compounds exhibit interesting properties in several application areas. In this regard, chemical preparation and characterization by X-ray diffraction, thermal analysis, and IR spectroscopy are given for a new organic cation diphosphate [4-CH3OC6H4CH2NH3]4P2O7·6H2O. This later crystallizes in a C2/c unit cell with a = 38.238(6)Å, b = 6.453(1)Å, c = 16.942(7)Å; β = 97.60(4)°; Z = 4; and V = 4144(2)Å3 and Dx = 1.377 g·cm?3. Its crystal structure has been determinated and refined to R = 0.044, using 7978 independent reflections. This atomic arrangement consists of inorganic layers built up from P2O7 4? anions and water molecules. On these layers, which are parallel to the (b, c) planes, the (4-CH3OC6H4CH2NH3)+ cations are anchored through multiple hydrogen bonds.  相似文献   

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