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1.
Fengxing Jiang Liangying Wang Changcun Li Xiaodong Wang Yongjing Hu Huixuan Liu Hui Yang Feng Zhao Jingkun Xu 《Journal of Polymer Research》2017,24(5):68
Organic thermoelectric materials based on conducting polymers, especially for polyaniline (PANi) and poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), have attracted great concern due to their tunable electron transport properties by controlling doping level. Here, the solvent effects of deionized H2O and NH3·H2O were investigated on the electrical conductivity and Seebeck coefficient of PANi/PEDOT/PSS composite films. The introduction of PEDOT/PSS can not only effectively improve the quality of pure PANi film, but also enhance the electrical conductivity of PANi film. The different volumes of deionized H2O as dilution have a great influence on the electrical conductivity of PANi/PEDOT/PSS composite thin film with a maximum electrical conductivity value of 63.5 S cm?1, which is much higher than pure PANi and pristine PEDOT/PSS. The introduction of NH3·H2O shows a positive effect on Seebeck coefficient with a large decline on electrical conductivity of PANi/PEDOT/PSS. The Raman spectroscopy, scanning electron microscopy (SEM), and UV-vis spectroscopy were used to obtain the morphology and structure information of PANi/PEDOT/PSS. 相似文献
2.
The performance at room temperature of nanostructured polyaniline (PANi)–titanium dioxide (TiO2) ammonia gas sensors was investigated. The PANi–TiO2 thin-film sensors were fabricated with a spin-coating method on glass substrates. PANi–TiO2 (0–50%) sensor films were characterized for their structural, morphological, optical, and various gas-sensing properties. The structural analysis showed the formation of nanocrystalline TiO2, whereas PANi exhibited an amorphous nature. Morphological analysis of the PANi–TiO2 nanocomposites film revealed a uniform distribution of TiO2 nanoparticles in the PANi matrix. The absorption peaks in the Fourier transform infrared spectra and ultraviolet–visible spectra of the PANi–TiO2 composite film were found to shift to higher wave numbers compared to those observed in pure PANi. The observed shifts were attributed to the interaction between the TiO2 particles and the PANi molecular chains. The gas-sensing properties showed that the sensors exhibited selectivity to ammonia (NH3) at room temperature. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
3.
Composite films from polyaniline (PANi) and polyurethane (PU), with flexibility and mechanical strength similar to pure PU and conductivity close to pure PANi, have been obtained by electropolymerizing amiline on a PU/Pt electrode in water/acetonitrile/ethylen glycol electrolyte solution. In the composite films, PANi is dispersed, in the form of particulate, inside and on the inner surface of the PU substrates. It is found that the electropolymerization reaction of aniline proceeds much faster in basic solution and composite film as prepared shows higher conductivity than that in acidic solution. PANi in PU/PANi composite film is protonic-acid-doped and is conducting even in case it is electropolymerized in a basic electrolyte solution. 相似文献
4.
《国际聚合物材料杂志》2012,61(3):244-254
Thin films of polyaniline (PANi) and PANi: titanium oxide (TiO2) composites have been synthesized by sol–gel spin coating technique. The TiO2 powder of particle size 50–60 nm was synthesized by the sol–gel technique and the polyaniline was synthesized by the chemical oxidative polymerization of aniline. The composite films were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, UV-vis spectroscopy and the four-probe method. The results were compared with corresponding data on pure polyaniline films. The intensity of diffraction peaks for PANi:TiO2 composites is lower than that for TiO2. The characteristic FTIR peaks of pure PANi are observed to shift to a higher wavenumber in PANi:TiO2 composite, which is attributed to the interaction of TiO2 particles with PANi molecular chains. The resistivity measurement shows that the molecular chain constitution of polyaniline is the most important carrier in the polyaniline: nano-TiO2 composite. 相似文献
5.
Thomas W. Dekleva Ajey M. Joshi Ian S. Thorburn Brian R. James Stephen V. Evans James Trotter 《Israel journal of chemistry》1990,30(4):343-350
The ruthenium (II) diene complexes [Ru(X)(Cl)(nbd)(dppb)] (X = Cl, H; nbd = 2,5-norbornadiene; dppb = PPh2(CH2)4PPh2) have been prepared and characterized spectroscopically. The X-ray crystal structure of RuCl2(nbd)(dppb) (crystal data at 22°C: space group P1, a = 10.896 (1) Å, b = 15.168(2) Å, c = 10.829 (1) Å, α = 103.02(1)°, β = 107.08(1)°, γ = 81.65(1)°, Z = 2, R = 0.054 for 6420 reflections) shows an octahedral geometry at Ru, with the chloro ligands slightly distorted from a trans configuration (Cl)(1)-Ru-C1(2) = 168.4°); the unit cell contains two molecules of the complex and one molecule of benzene. Reaction of this complex with H2, in presence of Proton Sponge (PS, 1,8-bis(dimethylamino)naphthalene) as base, is complicated by initial dissociation of nbd, and [Ru2Cl5(dppb)2]−-PSH+ is the major product. A minor product, the hydrido(diene) complex trans-RuCl(nbd)(dppb) 5 , characterized spectroscopically, is more effectively synthesized from (a) trans-Ru(H)Cl(nbd)(PPh3)2, 1 , and dppb, or (b) reaction of RuCl2(dppb)-(PPh3) with H2 in presence of nbd and PS. Complex 5 is unreactive toward H2 or CO while 1 has been shown previously to give η2-H2 and norbornenoyl derivatives, respectively; the differences in reactivity are discussed. 相似文献
6.
《国际聚合物材料杂志》2012,61(10):777-785
Thin films of polyaniline (PANi) and PANi:titanium oxide (TiO2) composites have been synthesized by sol—gel spin coating technique. The TiO2 powder of particle size 50–60 nm was synthesized by sol–gel technique and the polyaniline was synthesized by chemical oxidative polymerization of aniline. The composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) Fourier transform infrared (FTIR) and UV-vis spectroscopy, and the results were compared with polyaniline films. The intensity of the diffraction peaks for PANi:TiO2 composites is lower than that for TiO2. The characteristic FTIR peaks of PANi were found to shift to a higher wave number in the PANi:TiO2 composite. These observed effects have been attributed to the interaction of TiO2 particles with PANi molecular chains. The room temperature resistivity of polyaniline:nano-TiO2 composite is 3.43 × 103 Ω cm and the resistivity of pure nano-TiO2 particles is 1.60 × 106 Ω cm. 相似文献
7.
Marystela Ferreira Carlos J.L. Constantino Débora T. Balogh Roberto M. Faria 《Polymer》2005,46(14):5140-5148
A PPV derivative, poly(2-methoxy,5-(n-octadecyl)-p-phenylenevinylene) (OC1OC18-PPV), has been synthesized via the Gilch route and used to fabricate Langmuir and Langmuir-Blodgett (LB) films. True monomolecular films were formed at the air/water interface, which were successfully transferred onto different types of substrate. Using UV-visible absorption, FTIR, fluorescence and Raman scattering spectroscopies we observed that the polymer molecules were randomly distributed in the LB film, with no detectable anisotropy. This is in contrast to the anisotropic LB films of a previously reported PPV derivative, poly(2-methoxy-5-n-hexyloxy)-p-phenylenevinylene (OC1OC6-PPV), which is surprising because the longer chain of OC1OC18-PPV investigated here was expected to lead to more ordered films. As a consequence of the lack of order, LB films of OC1OC18-PPV exhibit lower photoconductivity and require higher operating voltage in a polymer light-emitting diode (PLED) in comparison with LB films of OC1OC6-PPV. This result confirms the importance of molecular organization in the LB film to obtain efficient PLEDs. 相似文献
8.
《Inorganic chemistry communications》2002,5(5):351-354
The reactivity of mononuclear platinum and palladium dithiolato species as building blocks for homo- and heterobimetallic complexes is described. The heterobimetallic cationic complex [(PPh3)2Pt(μ-S(CH2)2S)Pd(dppb)](BF4)2 was obtained by reaction of [Pt(S(CH2)2S)(PPh3)2] with [PdCl2(Ph2P(CH2)4PPh2)] in presence of AgBF4. 相似文献
9.
We report the preparation of Langmuir-Blodgett (LB) films composed of oxidized carbon nanotubes (CNTs) and hydrogenase (H2ase) conjugates and their electrochemical properties. Both single-walled (SWNTs) and multi-walled CNTs (MWNTs) were used to form mixed monolayers with H2ase on the Tris-HCl subphase surfaces. By using the LB method, the CNTs-H2ase monolayers were transferred onto CaF2 and indium tin oxide (ITO) electrode surfaces. The LB film modified electrodes showed a couple of waves centered at around −500 mV (versus Ag/AgCl), which corresponding to the redox reaction of [4Fe-4S]2+/1+ clusters in the H2ase. The current intensity was enhanced after co-assembly with CNTs. Because of the different diameters of CNTs, this current intensity was proportional to the scan rate (υ) for the electrodes modified with the LB films of pure H2ase and SWNTs-H2ase, but to the root of scan rate (υ1/2) for those modified with the MWNTs-H2ase LB film. The products of diffusion coefficient and concentration (D1/2C) increased in the order of pure H2ase, SWNTs-H2ase, and MWNTs-H2ase LB films. 相似文献
10.
Carlos Díaz Valenzuela Gabino A. Carriedo M. Luisa Valenzuela Luis Zú?iga Colm O‘Dwyer 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(2):447-454
The pyrolysis of several physical mixtures of AuCl(PPh3) with polymeric [NP(O2C12H8)]n or cyclic N3P3(O2C12H8)3 phosphazenes, formed as solid powders or films with different molar ratios, have been studied under air and at 800 °C. The
characterization of the products has shown that the particle size and morphology are strongly dependent on the nature of the
phosphazene, the phosphazene/AuCl(PPh3) molar ratio and on the preparation methodology. Gold nanoparticles (NPs) with mean sizes as small as 3.5 nm were obtained
from a [NP(O2C12H8)]n/AuCl(PPh3) 1:1 film. The particle morphology was also strongly dependent on the experimentally conditions of the pyrolysis. Powdered
materials exhibit a 3-D irregular morphology in the mixture [NP(O2C12H8)]n/AuCl(PPh3) 3:1 film, and gold foams in the 1:1 ratio, both from the [NP(O2C12H8)]n/AuCl(PPh3) as well as N3P3(O2C12H8)3/AuCl(PPh3) mixtures. These results show for the first time the possibility of controlling morphology and size of gold particles obtained
by solid-state reactions. 相似文献
11.
The novel set of quinazoline-based chiral ligands was synthesized starting from optically pure amino acids. Coordination with RuCl2(PPh3)dppb gave ruthenium(II) N-heterocyclic complexes 4b–d. The structure of complex 4b was fully illuminated by X-ray crystallography. The steric environment of these chiral ruthenium complexes 4b–d was evaluated in asymmetric transfer hydrogenation (ATH) of prochiral ketones in the presence of NaOiPr by using 2-propanol as the hydrogen source and solvent. The resultant catalytic system can achieve very good enantioselectivities (up to 91%) and high yields (up to 99%). 相似文献
12.
《Ceramics International》2016,42(13):15023-15029
Here we present an easy-reproducible microwave-assisted hydrothermal route for preparing pure nanocrystalline CeO2 films. The produced materials were characterized using a wide range of techniques (X-ray diffraction, field emission gun scanning electron microscopy, Raman spectroscopy) to understand the synthesis dependent changes in crystallographic structure, and crystallite size. Raman and X-ray diffraction techniques revealed that the films were free of secondary phases and that they crystallize in the cubic structure. The observed hydrodynamic particle size larger than the crystallite size confirms the aggregation phenomenon. Gas sensing measurements have been carried out to rationalize the type and number of surface adsorbed groups and overall nanostructure. Electrical conductance variations, owing to gases adsorption onto semiconductor oxide films surfaces, were observed in this work. Chemiresistive CeO2 film properties depend on the intergranular barrier heights and width. 相似文献
13.
Yun Heum Park Seong Yoon Park Sung Woo Nam Chong Rae Park Young Jun Kim 《应用聚合物科学杂志》1996,60(6):865-870
Electrically conducting arachidic acid/polypyrrole (PPy) composite films were prepared by exposing the arachidic acid LB films containing ferric chloride to pyrrole vapor. The optimum conditions to deposit matrix LB film were the subphase temperature of 23–25°C, pH of 6.0 and ferric chloride concentration of 5.0 × 10−5 M. The formation of PPy in the arachidic acid matrix LB films was confirmed by UV-visible spectra, FTIR spectra, and scanning electron micrographs. The average thickness of the composite LB films prepared at 0°C was 1525 Å. The composite films prepared at lower temperatures have more uniform surface and exhibit higher electrical conductivity than the films prepared at higher temperatures do. The in-plain conductivity and the transverse conductivity of the composite film were 10−3−10−2 S/cm and 10−6S/cm, respectively, and, thus, the conductivity anisotropy was about 103 © 1996 John Wiley & Sons, Inc. 相似文献
14.
Vanadium pentoxide/polyaniline (V2O5/PANi) composite films were prepared by a two-step electrochemical method and evaluated for their application in lithium batteries. As a first step the PANi film was potentiodynamically grown in an acid solution containing aniline monomer, and secondly vanadium oxide was oxidatively deposited on the polyaniline film in a temperature controlled VOSO4 solution. The increased current efficiency obtained with the larger anodic current in the high temperature solutions results in high contents of V2O5 in the composites, even if the oxidative dissolution of PANi also occurs. The large value of the diffusion coefficient estimated from the cyclic voltammograms for the composite film provides evidence for the synergistic effect of the conducting polymer and the inorganic composite. The cell exhibited excellent cycle stability with a high charge storage capacity. The large increase in the specific capacity for the composite film prepared in this work demonstrates that the conducting polymer in the composite acts as a binding and conducting element by contributing its electroactivity. The V2O5/PANi composite film cathodes show a large specific capacity (ca. 270 mAh/g) and improved cyclability with an extremely small amount of capacity fading (ca. 3.4%) during repeated charge/discharge cycles. 相似文献
15.
Shalendra Kumar Faheem Ahmed M.S. Anwar B.H. Koo H.K. Choi S. Gautam K.H. Chae Hanshik Chung 《Ceramics International》2013,39(2):1645-1650
Thin films of pure and Ti doped Mg0.95Mn0.05Fe2O4 deposited using pulsed laser deposition technique, have been characterized using X-ray diffraction, Raman spectroscopy, dc magnetization, atomic force microscopy, magnetic force microscopy and near edge X-ray absorption fine structure spectroscopy measurements. X-ray diffraction and Raman spectroscopy measurements indicate that both the films have single phase and the polycrystalline behavior with FCC structure. The grain size calculated using XRD data was 18 and 27 nm for pure and Ti doped films, respectively. Magnetic measurements reflect that pure film has superparamagnetic behavior while Ti doped film has soft ferrimagnetic behavior at room temperature. Atomic force microscopy measurements indicate that both the films are nanocrystalline in nature. Near edge X-ray absorption fine structure spectroscopy measurements clearly infer that Fe ions are in mixed valence state. 相似文献
16.
R. Jiménez A. del Campo M.L. Calzada J. Sanz S.D. Kobylianska B.O. Liniova A.G. Belous А.V. Ragulya 《Journal of the European Ceramic Society》2018,38(4):1679-1687
In this work, the influence of different thermal sintering treatments on Li1.3Al0.3Ti1.7(PO4)3 NASICON thick films has been investigated. The isostatic lamination step performed before the thermal sintering of thick films has demonstrated to improve film density and grain size, increasing "bulk" and grain boundary Li-conductivities. The confocal Raman spectroscopy characterization allowed the observation of the connectivity of the particles present in the ceramic samples and so a deeper understanding of ionic conductivity. The dependence of total and "bulk" Li conductivity on the samples microstructure is discussed. The films sintered by slow heating sintering with a previous lamination step, displayed an overall Li- conductivity >10?4 Ω-1 cm-1, that is superior to that reported in commercial OHARA Li- NASICON glass ceramics. The tape casting deposition method is scalable for preparation of large area thick supported electrolyte films with high conductivity for novel Li ion all solid state batteries (ASSB) architectures. 相似文献
17.
《Ceramics International》2021,47(20):28429-28436
Porous pure and Pd-doped SnO2 films are prepared using sol-gel synthesis with polystyrene (PS) microspheres as the template. Different characterizations are performed to analyze the microstructure and morphology of the films. The sensing performance of the films at various temperatures and hydrogen concentrations is investigated. Results show that high concentration of PS template significantly influences the continuity of films and the H2 sensing performance. The porous SnO2 film with 0.1 wt% PS microspheres exhibits the best performance. At 225 °C, the response magnitude of the porous 1 mol% Pd-doped SnO2 thin film to 1000 ppm H2 is 93.18, which is approximately 10.58 times of the pure sample. 相似文献
18.
Juan Reyes-LabartaMiguel Herrero Pilar TiembloCarmen Mijangos Helmut Reinecke 《Polymer》2003,44(8):2263-2269
The chemical modification of plasticized PVC films with amino thiophenol in mixtures of DMF/H20 has been studied. The degree of modification and the distribution of modified groups within the films were determined using Raman spectroscopy and FTIR-ATR. The amounts of plasticizer (bis-2-ethylhexyl phtalate, DOP) bleached out during the reaction and the amount of dimethylformamide (DMF) penetrated into the film were analysed in control reactions without the reactant using 1H NMR spectroscopy and Raman spectroscopy.Reaction kinetics and surface selectivity of the modification reaction were compared with the corresponding reactions of PVC films without plasticizer. 相似文献
19.
Polyaniline (PANi), poly(2-chloroaniline) (PClANi), and poly(aniline-co-2-chloroaniline) (co-PClANi) films were synthesized by electrochemical deposition on 304-stainless steel (SS) from an acetonitrile solution. The structural properties of these polymer films were characterized by spectroscopic (FTIR and UV–vis) and electrochemical (cyclic voltammetry) methods. Open circuit potential–time (Eocp–time) curves, potentiodynamic polarization, and electrochemical impedance (EIS) measurements showed that these films have significant protective performance against corrosion of SS in 0.5 M HCl solution. It was found that co-PClANi film has acted as a passivator as well as barrier for cathodic reduction reaction in a similar manner as PANi film. However, PClANi film has behaved only as barrier for corrosion protection of SS in 0.5 M HCl. 相似文献
20.
Zhen-Rui Gu Hui Fu Li Liu Fa-Bao Li Shi-Zhong Liu Yan-Rong Wang Zu-Liang Du Cheuk-Lam Ho Wai-Yeung Wong 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(3):665-672
A new series of organic/inorganic composite Langmuir–Blodgett (LB) films consisting of 2-aminofluorene (Fl–NH2) as the π-conjugated organic molecule, an europium-substituted polyoxometalate (POM, POM = Na9EuW10O36, K13[Eu(SiW11O39)2] and K5[Eu(SiW11O39)(H2O)2], which are denoted by EuW10, EuW22 and EuW11, respectively) as the inorganic component, were prepared. Structural and photophysical characterization of these LB films were achieved by π–A isotherms, UV–Vis absorption and photoluminescence spectra, atomic force microscopy imaging, scanning tunneling microscopy, and surface photovoltage spectroscopy. Our experimental results indicate that stable Langmuir and LB films are formed in pure water and POM sub-phases. Luminescence spectra of the prepared hybrid LB films show that tunable emission color can be obtained due to the dual-emissive nature of the mixed Fl–NH2/POM blends. These 2-aminofluorene-based LB films displayed interesting electrical conductivity behavior. Among them, Fl–NH2/EuW11 3-layer films showed a good electrical response with the a tunneling current up to ± 100 nA when the voltage was monitored at ?0.8 to 1.5 V. These LB composites show good photovoltage responses and a photovoltage of 2.7 μV can be obtained for the Fl–NH2/EuW22 system when it is excited by light. 相似文献