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1.
Novel ferromagnetic semiconducting polyaniline PANI/TiO2 nanocomposites were synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in an aqueous medium, in the presence of colloidal TiO2 nanoparticles (d ∼ 4.5 nm), without added acid. The morphological, magnetic, structural, and optical properties of the PANI/TiO2 nanocomposites prepared at initial aniline/TiO2 mole ratios 80, 40, and 20 were studied by scanning electron microscopy, superconducting quantum interference device, X‐ray powder diffraction, FTIR, Raman, and UV‐Vis spectroscopies. The emeraldine salt form of linear PANI chains as well as the presence of phenazine units, branched PANI chains, and anatase crystalline structure of TiO2 in PANI/TiO2 nanocomposites was confirmed by FTIR and Raman spectroscopies. The electrical conductivity of synthesized composites was ∼10−3 S cm−1. The room temperature ferromagnetic response with coercive field of Hc ∼ 300 Oe and the remanent magnetization of Mr ∼ 4.35 × 10−4 emu/g was detected in all investigated PANI/TiO2 nanocomposites. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers  相似文献   

2.
Nowadays, nanocomposites are a special class of materials having unique physical properties and wide application potential in diverse areas. The present research work describes an efficient method for synthesis of a series of polypyrrole/titanium dioxide (PPy/TiO2) nanocomposites with different TiO2 ratios. These nanocomposites were prepared by one‐step in situ deposition oxidative polymerization of pyrrole hydrochloride using ferric chloride (FeCl3) as an oxidant in the presence of ultra fine grade powder of anatase TiO2 nanoparticles cooled in an ice bath. The obtained nanocomposites were characterized by Fourier‐transform infrared (FTIR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and scanning electron microscope (SEM) techniques. The obtained results showed that TiO2 nanoparticles have been encapsulated by PPy with a strong effect on the morphology of PPy/TiO2 nanocomposites. Also, the synthesized PPy/TiO2 nanocomposites had higher thermal stability than that of pure PPy. The investigation of electrical conductivity of nanocomposites by four‐point probe instrument showed that the conductivity of nanocomposite at low TiO2 content is much higher than of neat PPy, while with the increasing contents of TiO2, the conductivity decreases. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

3.
Binary doped polypyrrole (PPy) encapsulated Titania (TiO2) nanoparticles were prepared by oxidative polymerization using FeCl3 as oxidant in presence of camphorsulfonic acid (CSA) as surfactant. Both FeCl3 (oxidant) and camphorsulfonic acid (surfactant) also act as dopant and hence thus prepared polypyrrole/Titania (TiO2@PPy) is termed as binary doped nanocomposite i.e. FeCl3 dopes polypyrrole by oxidation mechanism while camphorsulfonic acid dopes polypyrrole by protonic doping mechanism. The TiO2@PPy coreshell nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), thermogravimetry, differential scanning calorimetry (DSC), field emission‐scanning electron microscopy (FE‐SEM), and inductance‐capacitance‐resistance (LCR) measurements. The results indicated that the structural and electrical properties of the TiO2@PPy coreshell nanocomposites were significantly influenced by the extent of TiO2 nanoparticles loading of polypyrrole. The direct current (DC) electrical conductivity of the as‐prepared TiO2@PPy coreshell nanocomposites was higher than that of PPy. As‐prepared TiO2@PPy coreshell nanocomposites were also studied for their dielectric losses for alternating current (AC) which is useful characteristic for their application in the fabrication of charge storing devices. TiO2@PPy coreshell nanocomposites showed synergistic effect of combining components in improving their alcohol sensing properties. This improvement may be attributed to the adsorption on and desorption from alcohols TiO2@PPy interface of the nanocomposites and alcohol vapors causing decrease in depletion region. The TiO2@PPy coreshell nanocomposites were observed to show better reproducibility of electrical conductivity and fast self‐recovery during the alcohol vapor sensing process. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43411.  相似文献   

4.
PPy/TiO2 nanocomposites were successfully prepared by reverse microemulsion polymerization and used as an effective photocatalyst for the degradation of methyl orange. Titanium dioxide (TiO2) was modified by silane coupling agent to improve the dispersity before the polymerization. X‐ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier‐transform infrared spectra were carried out to characterize the morphology and structure of the samples. TEM analysis shows that TiO2 particles are deposited by polypyrrole (PPy) and the existence of PPy mitigates the agglomeration of TiO2. XRD spectra reveal that the deposition of PPy does not change the structure of TiO2 particles. Uv–vis analysis shows that the PPy/TiO2 nanocomposites have a higher photocatalytic activity under natural light than neat TiO2. The highest degradation rate occurs when the mass ratio of PPy to TiO2 is kept at 0.02. POLYM. COMPOS., 34:1076–1080, 2013. © 2013 Society of Plastics Engineers  相似文献   

5.
《Ceramics International》2016,42(5):5766-5771
In this work, TiO2–reduced graphene oxide (RGO) nanocomposites were successfully produced by an ultrasonication-assisted reduction process. The reduction of graphene oxide (GO) and the formation TiO2 crystals occurred simultaneously. The synthesized nanocomposite was characterized by SEM, EDX, Raman spectroscopy, FTIR, XRD, XPS, UV–vis spectroscopy, photoluminescence spectrometer and electrochemical impedance spectroscopy. As a result of the introduction of RGO, the light absorption of octahedral TiO2 was markedly improved. The photocatalytic results revealed that weight percent of RGO has substantial influence on degradation of Rhodamine B under visible light irradiation. The enhancement of the photocatalytic activity can be attributed to the enhancement of the visible-light irradiation harvesting and efficiently separation of the photogenerated charge carriers. Meanwhile, upon the RGO loading, the photoelectric conversion efficiency of TiO2–RGO nanocomposite modified electrode was also highly improved.  相似文献   

6.
A facile method to prepare uniform polypyrrole (PPy) nanospheres is developed by using 3-chloroperbenzoic acid as oxidant, structure-induced reagent and dopant for polymerization of pyrrole without introducing extra acid, template and surfactant. The as-synthesized PPy nanospheres with an average diameter of 100–200 nm and conductivity about 10−2 S cm−1 are characterized by SEM, FTIR, UV–vis spectroscopy, XRD and elemental analysis in an effort to determine the identity of the nanospheres and the mechanism relevant to their formation and stabilization. Influences of experimental conditions on the morphology of the PPy nanospheres have been investigated. Via the high temperature pyrolyzation at 900 °C, the nitrogen-doped carbon nanospheres have been obtained from the PPy nanospheres precursors, which have a high conductivity of 10–100 S cm−1, showing a good potential as the electrode materials for high-performance supercapacitors due to their excellent electrochemical performance.  相似文献   

7.
Conducting polyaniline (PANI)/titanium dioxide (TiO2) composite nanofibres with an average diameter of 80–100 nm were prepared by one‐step in situ polymerization method in the presence of anatase nano‐TiO2 particles, and were characterized via Fourier‐transform infrared spectra, UV/vis spectra, wide‐angle X‐ray diffraction, thermogravimetric analysis, and transmission electron microscopy, as well as conductivity and cyclic voltammetry. The formation mechanism of PANI/TiO2 composite nanofibres was also discussed. This composite contained ~ 65% conducting PANI by mass, with a conductivity of 1.42 S cm?1 at 25°C, and the conductivity of control PANI was 2.4 S cm?1 at 25°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

8.
ABSTRACT

Conjugated polymer/graphite nanocomposites have been known as high performance materials owing to improve the physicochemical properties relative to conventional once. Multilayered polymer nanocomposites based on polypyrrole (PPy), polyvinylchloride (PVC) as matrices and p-phenylene diamine (PDA) as linker were prepared via chemical in situ polymerization process and subsequently investigated the physical characteristics of fabricated nanocomposites at various loadings. The structural characterization and morphology of prepared nanocomposites were inspected by Fourier transform infrared spectroscopy (FTIR), X-ray photon spectroscopy (XPS), energy dispersive X-ray spectroscope (EDX), field emission scanning electron microscope (FESEM), respectively. The composite III showed higher thermal stability at 10 wt% loading of PPy. According to differential scanning calorimetry (DSC), the glass transition temperature (Tg), melting temperature Tm, and crystallization temperature (Tc) of nanocomposites increases with PPy loading (2–10 wt%) owing to crosslinking and chain rigidity. Moreover, higher surface area was displayed by the multilayered PPy/PVC/PDA@FG nanocomposites. Remarkably, electrical conductivity of ultimate nanocomposites was also found to be a function of PPy loading.  相似文献   

9.
We report the synthesis and characterization of new organic/inorganic hybrid materials constituted of Ni(0) and Cu(0) nanoparticles and polypyrrole (PPy). Copper and nickel nanoclusters were synthesized by a chemical reduction of aqueous metal salt solutions by sodium borohydride. PPy/Ni(0) and PPy/Cu(0) composites were obtained in the presence of two different acids (H3BO3, CH3COOH), by polymerizing pyrrole‐Ni and pyrrole‐Cu particles by using iron (III) chloride. The composites have been characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and magnetic susceptibility techniques. Conductivity measurements of samples were taken using four‐probe devices. The PPy/Ni(0) and PPy/Cu(0) nanocomposites doped with different acids exhibited higher conductivity values than those of homopolymers. Among all samples, Ni/PPy‐H3BO3 has the highest conductivity (1.42 S cm?1). Homopolymers and composites showed a stable and increasing conductivity with increasing temperature, except Ni(0). We observed that from TGA analysis of polymers, metal composites of PPy synthesized in two different media are more stable than those of PPy‐CH3COOH and PPy‐H3BO3. The magnetic susceptibility values of homopolymers and Cu are negative, whereas the other samples are positive. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

10.
《Ceramics International》2021,47(22):31927-31939
The goal of this study was to create highly efficient dye-sensitized solar cells (DSSCs) using strontium doped zinc oxide-reduced graphene oxide (Sr-doped ZnO/rGO) nanocomposites. As photo-anodes of DSSCs, ZnO, ZnO/rGO (with weight percent rGO in composites: 0, 0.01, 0.1, 0.5, and 1 wt%) and Sr-doped ZnO/rGO (with Zn1-xSrxO nanoparticle stoichiometry: x = 0, 0.02, 0.04, 0.06 and 0.08) nanocomposites were designed and characterized. AFM, FESEM, XRD, EDS, XPS, PL, and FTIR analyses were used to investigate the morphology and structure properties of prepared nanocomposites. UV–vis spectroscopy and photo-electrochemical measurements were used to investigate the efficiency of prepared photo-anodes. The efficiency (η) and short-circuit photocurrent density (JSC) of DSSCs based on Zn0.92Sr0.08O/rGO nanocomposite were 7.98 % and 18.4 mA cm−2, respectively. The results showed that doping Sr on ZnO/rGO nanocomposites resulted in a wide bandgap energy and increased the values of η, JSC, IPCE, and photo-anode electron transportability. These findings suggest that Sr-doped ZnO/rGO nanocomposites can provide a novel approach for increasing photo-electrochemical activity in ZnO-based DSSCs.  相似文献   

11.
The present study demonstrates a modified in situ emulsion polymerization (EP) approach convenient for the formation of polypyrrole/graphene (PPy/GN) nanocomposites with harnessed conductivities. A series of PPy/GN nanocomposites were prepared by loading different weight percent (wt %) of GN during in situ EP of pyrrole monomer. The polymerization was carried out in the presence of dodecyl benzene sulfonic acid, which acts as an emulsifier and protonating agent. The microstructures of the nanocomposites were studied by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, UV–vis spectroscopy, Raman spectroscopy, photoluminescence spectroscopy and thermogravimetric analyses. The electrical conductivities of the nanocomposite pellets pressed at different applied pressures were determined using four probe analyzer. The electrical conductivities of the nanocomposites were considerably enhanced as compared to those of the individual PPy samples pressed at the same pressures. An enhanced conductivity of 717.06 S m?1 was observed in the sample with 5 wt % GN loading and applied pressure of 8 tons. The results of the present study signify that the addition of GN in the PPy polymer harnesses both electrical and thermal properties of the polymer. Thus, PPy/GN nanocomposites with superior properties for various semiconductor applications can be obtained through direct loading of GN during the polymerization process. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41800.  相似文献   

12.
Rutile titanium dioxide (TiO2)/poly(methyl methacrylate‐acrylic acid‐butyl acrylate) nanocomposites were synthesized via seeded emulsion polymerization and characterized by Fourier transmission infrared, dynamic light scattering, X‐ray diffraction, ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis to study their UV‐shielding property. The effects of the nanoseed types, surfactant concentrations, and functional monomer amounts on the polymerization conversion, particle size, emulsion stability, and morphologies of the resulting nanocomposites were investigated. The dependence of UV‐shielding performance on the nanoparticle content and dispersion was also explored. The optimized results are obtained with 2 wt% of TiO2 nanoparticles addition, and the effectiveness of UV shielding is significantly increased by using the synthesized rutile nano‐TiO2/polyacrylates, for which the nanocomposite coating with a thickness of 200 μm could block up to 99.99% of UV light (≤350 nm) as confirmed by UV–vis spectrometry. POLYM. COMPOS., 36:8–16, 2015. © 2014 Society of Plastics Engineers  相似文献   

13.
In order to obtain efficient microwave absorbers that possess high conductivity, dielectric and magnetic properties, hexanoic acid doped polyaniline (PAni) nanocomposites which contain different ratios of ferum (II) oxide (Fe3O4) and titanium dioxide (TiO2) nanoparticles were successfully prepared by in situ chemical polymerization through template free method. Chemical structure, conductivity, morphology, thermal stability, magnetic properties, and amorphous/crystalline behavior of PAni nanocomposites were characterized by Fourier transform infrared spectrometer (FTIR), four point probe, field emission scanning electron microscope (FESEM), thermal gravimetric analysis (TGA), vibrating samples magnetometer (VSM), and X‐ray diffractometer (XRD), respectively. From this study, conductivity was significantly improved from 8.48 × 10−4−1.23 × 10−2 S/cm for PAni nanocomposites without any chemical treatment (during addition of Fe3O4) to 3.58 × 10−2−4.77 × 10−2 S/cm for those with chemical treatment. PAni nanocomposites with chemical treatment show a narrow sharp reflection loss (RL) peak with high absorption (−48.9 dB) at lower frequency due to the limited individual Fe3O4 nanoparticles outside the nanorods/nanotubes as proved by the new proposed mechanism (Fig. 5 ), while it shows a broad RL peak with poor absorption (−13 dB) at higher frequency for those without chemical treatment. The novelty of this research has been focused on PAni with chemical treatment which yield better microwave absorption property (99.999% absorption), combination of high conductivity (3.58 × 10−2−4.77 × 10−2 S/cm), high heterogeneity and moderate magnetization (Ms = 8.87–28.49 emu/g) compare to the PAni without chemical treatment. POLYM. COMPOS., 34:1186–1194, 2013. © 2013 Society of Plastics Engineers  相似文献   

14.
《Ceramics International》2020,46(1):663-671
Solid-state electrolytes Na2MTeO6 (M = MgNi and MgZn) were prepared via a conventional solid-state reaction method. Structural properties of the samples were investigated by using powder X-ray diffraction (XRD), Raman, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy (XPS) techniques. XPS and XRD studies indicate the phase pure hexagonal layered P2-type structure of samples. Raman and FTIR spectroscopy reveal the possible bending and stretching vibration modes for Te–O and other metal oxides. The ion transport properties of the solid electrolytes were investigated by using AC impedance spectroscopy. The electrical properties were examined by means of classical brick layer model. The specific grain conductivity (σg) is found to be 2.13 × 10−5 S cm−1 and 0.90 × 10−5 S cm−1 at 20 °C for Na2MgNiTeO6 and Na2MgZnTeO6 electrolytes, respectively. The activation energy of σg for Na2MgNiTeO6 and Na2MgZnTeO6 is found to be 0.59 eV and 0.36 eV respectively for the temperature below 30 °C. Summerfield AC conductivity scaling analysis of samples is performed. These electrolytes could be potential candidates in solid-state Na+ battery applications.  相似文献   

15.
Tieshi He  Fengmei Ren  Haihong Ma  Jin Wang 《Polymer》2009,50(13):3031-3036
The preparation and photocatalytic properties of titanium dioxide (TiO2)-fluoropolymer fiber nanocomposites were studied. The fluoropolymer nanofibers with carboxyl group were prepared by electrospinning. The complex was formed between carboxyl on fluoropolymer electrospun fiber surface and titanium ion, and then the TiO2 nanoparticles were immobilized on the surface of fluoropolymer electrospun fibers through hydrothermal complex-precipitation. By controlling the reaction conditions, different sizes and numbers of TiO2 nanocrystals can be obtained. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results reveal that an interaction exists between TiO2 and fluoropolymer fibers. The degradation of methylene blue solution is performed by TiO2-fluoropolymer fiber nanocomposites under UV irradiation. There may be an adsorption-migration-photodegradation process during the degradation of methylene blue by using TiO2-fluoropolymer fiber nanocomposites as photocatalyst. The experimental results show that the TiO2-fluoropolymer fiber nanocomposites have good photocatalytic ability, recycling and stability for the potential applicability in an environmental remediation.  相似文献   

16.
Nanocomposites based on neodymium‐doped titanium dioxide (Nd‐TiO2)/poly(n‐butyl methacrylate) (PBMA) have been prepared by an in situ polymerization of butyl methacrylate monomer with varying concentrations of Nd‐TiO2 nanoparticles. The resulting nanocomposites have been analyzed by ultraviolet (UV)–Visible spectroscopy, Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis, and impedance analyzer (TGA). The results of UV and FTIR spectroscopy have indicated the interaction of nanoparticles with the PBMA matrix. Spherically shaped nanoparticles with an average size of 10–25 nm have been revealed in the TEM and their homogeneous dispersion, and interaction of polymer matrix has been confirmed by SEM and XRD studies. The thermal stability and glass transition temperature of the composites were significantly enhanced by the addition of nanoparticles. The AC conductivity and dielectric properties of nanocomposites have been found to be higher than pure PBMA, and the maximum electrical properties have been observed for 7 wt% composite. The reinforcing nature of the nanoparticles in PBMA has been reflected in the improvement in tensile strength measurements. The result indicated that the tensile strength of nanocomposites have greatly enhanced by the addition of Nd‐TiO2 nanoparticles whereas the elongation at break decreases with the loading of nanofillers. To understand the mechanism of reinforcement, tensile strength values have been correlated with various theoretical modeling. The research has been found to be promising in the development of novel materials with enhanced tensile strength, dielectric constant, and thermal properties, which may find potential applications in energy storage and nanoelectronic devices. J. VINYL ADDIT. TECHNOL., 25:9–18, 2019. © 2018 Society of Plastics Engineers  相似文献   

17.
Nanocomposites of iron oxide (Fe3O4) with a sulfonated polyaniline, poly(aniline‐co‐aminonaphthalenesulfonic acid) [SPAN(ANSA)], were synthesized through chemical oxidative copolymerization of aniline and 5‐amino‐2‐naphthalenesulfonic acid/1‐amino‐5‐naphthalenesulfonic acid in the presence of Fe3O4 nanoparticles. The nanocomposites [Fe3O4/SPAN(ANSA)‐NCs] were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, elemental analysis, UV–visible spectroscopy, thermogravimetric analysis (TGA), superconductor quantum interference device (SQUID), and electrical conductivity measurements. The TEM images reveal that nanocrystalline Fe3O4 particles were homogeneously incorporated within the polymer matrix with the sizes in the range of 10–15 nm. XRD pattern reveals that pure Fe3O4 particles are having spinel structure, and nanocomposites are more crystalline in comparison to pristine polymers. Differential thermogravimetric (DTG) curves obtained through TGA informs that polymer chains in the composites have better thermal stability than that of the pristine copolymers. FTIR spectra provide information on the structure of the composites. The conductivity of the nanocomposites (~ 0.5 S cm?1) is higher than that of pristine PANI (~ 10?3 S cm?1). The charge transport behavior of the composites is explained through temperature difference of conductivity. The temperature dependence of conductivity fits with the quasi‐1D variable range hopping (quasi‐1D VRH) model. SQUID analysis reveals that the composites show ferromagnetic behavior at room temperature. The maximum saturation magnetization of the composite is 9.7 emu g?1. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

18.
A poly(aniline‐co‐pyrrole), using anionic spherical polyelectrolyte brushes (ASPB) as dopant and template, was synthesized by chemical oxidation polymerization. The composites were characterized by scanning electron microscopy (SEM), Fourier‐transform infrared spectrometry (FTIR), X‐ray diffraction (XRD), and electrical studies. The SEM images confirmed that the composites had a spherical‐like structure, with a size of ca. 170 nm. The FTIR spectra showed the intermolecular interaction between poly(aniline‐co‐pyrrole) and ASPB. The XRD analysis revealed that the interplanar distance of the copolymers increased from 0.373 nm to 0.391 nm. The electrical conductivity of the poly(aniline‐co‐pyrrole)/ASPB nanocomposites at room temperature was 8.3 S cm−1, higher than that of the conducting copolymers (2.1 S cm−1). These conductive nanocomposites have nanoparticle size, controllable morphology, and the potential for application in inkjet electronic printing. POLYM. COMPOS., 35:1858–1863, 2014. © 2014 Society of Plastics Engineers  相似文献   

19.
The polymeric blend was fabricated with crystalline poly(vinylidene fluoride) (PVDF)/amorphous functionalized-poly(methyl methacrylate) (PMMA) in 70/30 w/w ratio by chemical mixing method. Functionalization of PMMA was achieved with 2-amino-5-nitrobenzoic acid. The prepared polymer blend was used as a matrix to synthesize nanocomposites with undoped/doped zinc oxide (ZnO) nanoparticles. Doping in ZnO was achieved with vanadium, sulfur, and dysprosium elements as a dopant. The structural, optical, electronic, and morphological properties of undoped/doped nanosized ZnO and blended nanocomposites were accessed through sophisticated analytical techniques, that is, Fourier transform infrared (FTIR), ultraviolet–visible (UV–vis), UV–vis–diffuse reflectance spectra, nuclear magnetic resonance, fluorescence spectroscopy, X-ray diffraction (XRD), transmission electron microscopy, and scanning electron microscopy. The FTIR band at 1165–1176 cm−1 in functionalized-PMMA indicate the formation of aliphatic C-N bond along with aromatic 1H chemical shift (δ) at 7.134, 7.829 and 8.210 ppm confirm the successfully functionalization of PMMA. The prominent XRD peak at 2θ = 20.8° in nanocomposites shown improvement in β-phase of PVDF. The results show that Dy doped ZnO nanoparticles create remarkable effect on various properties of nanocomposites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47116.  相似文献   

20.
Silver and zirconium co‐doped and mono‐doped titania nanocomposites were synthesized and deposited onto polyacrylonitrile fibers via sol–gel dip‐coating method. The resulted coated‐fibers were characterized by X‐ray diffraction (XRD), scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, diffuse reflectance spectroscopy, thermogravimetric analysis, and BET surface area measurement. Photocatalytic activity of the TiO2‐coated and TiO2‐doped coated fibers were determined by photomineralization of methylene blue and Eosin Y under UV–vis light. The progress of photodegradation of dyes was monitored by diffuse reflectance spectroscopy. The XRD results of samples indicate that the TiO2, Ag‐TiO2, Zr‐TiO2, and Ag‐Zr‐TiO2 consist of anatase phase. All samples demonstrated photo‐assisted self‐cleaning properties when exposed to UV–vis irradiation. Evaluated by decomposing dyes, photocatalytic activity of Ag–Zr co‐doped TiO2 coated fiber was obviously higher than that of pure TiO2 and mono‐doped TiO2. Our results showed that the synergistic action between the silver and zirconium species in the Ag‐Zr TiO2 nanocomposite is due to both the structural and electronic properties of the photoactive anatase phase. These results clearly indicate that modification of semiconductor photocatalyst by co‐doping process is an effective method for increasing the photocatalytic activity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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