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1.
Magdalena Staszewska Monika Dzieciuch Joanna Lewandowska Mariusz Kepczynski Szczepan Zapotoczny Marcin Oszajca Anna Łatkiewicz Maria Nowakowska 《Journal of Sol-Gel Science and Technology》2011,59(2):276-282
In this article, we report on the formation of well-defined highly emissive silica-covered porphyrin microstructures in base-catalyzed
sol–gel processes. The microstructures were obtained by self-assembly of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (mTHPP)
at room temperature. Tetraethoxysilane (TEOS) was used as a silica precursor. The hybrid mTHPP- silica particles were characterized
by means of reflectance UV–Vis and microscopy techniques including atomic force microscopy, scanning electron microscopy (SEM)
and confocal fluorescence microscopy (CM). The SEM and TEM observations revealed that depending on the porphyrin concentration
used in the synthesis, the shape of the hybrid mTHPP-silica particles has changed from ribbon-like (c
mTHPP = 2.09 mM) to rhombus-like structures (c
mTHPP = 4.35 mM). The ribbons were straight-edged, uniform in width (1.2–1.8 μm) and height (350–400 nm), and variable in length
(40–100 μm). The rhombs were 1–3.7 μm in height, 7–25 μm in length, and 3.5–15 μm in width, and the ratio of length to width
was uniform and equal to ca. 1.8–2. UV–Vis absorption spectra indicated that the J-aggregates and H-aggregates formed in the
systems with lower and higher porphyrin content, respectively. Formation of different type of porphyrin aggregates in both
systems resulted in different emission spectra, as it was shown with CM. 相似文献
2.
Leticia M. Torres-Martínez Cecilia Sánchez-Trinidad Vicente Rodríguez-González Soo Wohn Lee Ricardo Gómez 《Research on Chemical Intermediates》2010,36(1):5-15
Indium-Na2Ti6O13 doped semiconductors were prepared by the sol–gel method using titanium and sodium alkoxides as precursors. The gelled samples
were annealed at 700 °C for 4, 6, and 8 h, and then characterized by X-ray diffraction (XRD), scanning electron microscopy
(SEM), energy-dispersive spectroscopy (EDS), and UV–Vis diffused reflectance spectroscopy (DRS). XRD patterns of the samples
show the formation of the Na2Ti6O13 phase, whose crystallinity depends on the annealing time. The band gap calculated from the UV–Vis Kubelka–Munk function report
similar values (3.2–3.4 eV) for all of the samples annealed at different times. SEM observations of the semiconductors showed
microfiber bundle morphologies of about 5 μm. Meanwhile, by EDS analysis, indium oxide highly homogeneously dispersed on the
hexatitanate surface was identified. The evaluation of the In-Na2Ti6O13 semiconductors in the 2,4-dichlorophenoxyacetic acid (2,4-D) photodecomposition using ultraviolet light (λ = 254 nm) irradiation show that the photoactivity of the solids depends on the annealing time applied to the samples. The
role of indium oxide is related to the indium oxide dispersed on the surface of the titanate diminishing the electron-hole
recombination rate. 相似文献
3.
Dalia Nayak Devdeep Mukherjee Aparna Banerjee Jhumpa Mukherjee 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):477-480
The present work discusses the complexation behavior of bioligand cysteine with cobalt and the immobilization of this complex
(Co–Cys) onto a biocompatible ligand and common drug base, polyvinylpyrrolidone (PVP). The complexation behavior has been
studied by radiometric method and UV–Vis spectrophotometry. The radiometric method involves dialysis of 60Co–Cys–PVP complex against triple distilled water which subsequently gives the dynamic dissociation constant (k
d) of the complex. The half life of 60Co–Cys–PVP complex calculated from k
d value is 22.6 h against triple distilled water at pH 8.5. The UV–Vis spectra analysis confirms the complexation of Co with
cysteine at this pH and also indicates that the cysteine ligated Co(II) centers easily get oxidised to Co(III) centers (low
spin, d6) in the presence of air at alkaline pH showing no d–d transitions. 相似文献
4.
Pietro Calandra Angela Ruggirello Alessandro Pistone Vincenzo Turco Liveri 《Journal of Cluster Science》2010,21(4):767-778
Stable dispersions of surfactant-coated TiO2–Ag based nanoparticles in apolar medium have been prepared by performing sequentially the hydrolysis of titanium(IV) isopropoxide
and the reduction of Ag+ in the confined space of sodium bis(2-ethylhexyl)sulfosuccinate (NaAOT) reverse micelles. Depending on the sequence length,
this novel procedure allowed the synthesis of semiconductor–metal nanoparticles, nominally indicated as TiO2/Ag, TiO2/Ag/TiO2, and TiO2/Ag/TiO2/Ag, stabilized by a monolayer of oriented surfactant molecules. The structural characterization of these nanoparticles has
been performed by High Resolution Transmission Electron Microscopy (HR-TEM), while optical properties were investigated by
UV–Vis absorption and fluorescence spectroscopies. TEM investigation showed the presence of globular nanoparticles with an
average diameter of about 10 nm composed by distinct amorphous TiO2 and crystalline Ag glued domains whose structure depends on the sequence length. UV–Vis absorption measurements highlighted
the mutual metal–semiconductor influence on the TiO2 energy band gap and on the Ag plasmon resonance. Steady-state fluorescence spectra analysis allowed to reveal the strong
inhibition of the electron–hole radiative recombination in the TiO2 domains due to the Ag and the appearance of a new emission band centred in the 484–545 nm range. Possible attributions of
the involved electronic transition of this last emission are discussed. 相似文献
5.
Nahid Shahabadi Soheila Kashanian Marzieh Khosravi Maryam Mahdavi 《Transition Metal Chemistry》2010,35(6):699-705
The water-soluble Ni(II) complex, [Ni(bipy)2(phen-dione)](OAc)2·2H2O (bipy = 2,2′-bipyridine and phen-dione = 1,10-phenanthroline-5,6-dione) has been synthesized and characterized by physico-chemical
and spectroscopic methods. The binding interactions of this complex with calf thymus DNA (CT-DNA) were investigated using
fluorimetry, spectrophotometry, circular dichroism and viscosimetry. In fluorimetric studies, the enthalpy and entropy of
the reaction between the complex and CT-DNA showed that the reaction is exothermic (ΔH = −123.9 kJ mol−1; ΔS = −323.5 J mol−1 K−1). The competitive binding studies showed that the complex could not release methylene blue completely. The complex showed
absorption hyperchromism in its UV–Vis spectrum with DNA. The calculated binding constant, K
b obtained from UV–Vis absorption studies was 2 × 105 M−1. Moreover, the complex induced detectable changes in the CD spectrum of CT-DNA, as well as changes in its viscosity. The
results suggest that this nickel(II) complex interact with CT-DNA via a groove-binding mode. 相似文献
6.
Two new complexes with formula VOL2·nH2O ((1) L: 4′,5,7-trihydroxyflavone-7-rhamnoglucoside (naringin), n = 8; (2) L: 3′,4′,7-tris[O-(2-hydroxyethyl)]rutin (troxerutin), n = 0) were synthesised and characterised. The IR and UV–Vis spectral data indicate that these flavones act as bidentate chelating
ligands and generate VO(II) complexes with a square-pyramidal stereochemistry. The thermal analysis (TG, DTA) elucidated the
composition and also the number and nature of the water molecules. The thermal behavior indicates also a strong interaction
between oxovanadium (IV) and these oxygen donor ligands. 相似文献
7.
Esposito Serena Setaro Antonio Maddalena Pasqualino Aronne Antonio Pernice Pasquale Laracca Marco 《Journal of Sol-Gel Science and Technology》2011,60(3):388-394
A modified sol–gel method was used to prepare cobalt doped silica thin film with a cobalt content of 10, 20 and 30 mol% (10Co, 20Co and 30Co). The prepared films were annealed at different temperatures in the range 400–1,000 °C, and their structural evolution examined.
The mixed valence cobalt oxide, Co3O4, crystallizes only in the sample with the higher cobalt content, while cobalt silicate is the only crystalline phase detected
in the sample 10Co and 20Co. Both the cobalt content and the temperature of heat treatment resulted to affect the nature of cobalt species dispersed
in the silica matrix. The 30Co was selected for further investigations by FTIR spectroscopy to follow the structural evolution of 30Co film as function of the temperature and UV–Vis to get information on the cobalt valence state. The optical gas-sensing properties
of 30Co films, containing Co3O4 as the major cobalt phase, were studied through the measuring of the film transmittance in dry air and in presence of dry
air containing variable concentrations of polluting gases, CO and NO2. The 30Co samples resulted to be highly sensitive to CO at room temperature. An explanation for the CO sensing characteristics, at
low temperature, was proposed by referring to the physisorption-related mechanics of CO. 相似文献
8.
The InVO4 sol was obtained by a mild hydrothermal treatment (the precursor precipitation solution at 423 K, for 4 h). Novel visible-light
activated photocatalytic InVO4–TiO2 thin films were synthesized through a sol–gel dipping method from the composite sol, which was obtained by mixing the low
temperature InVO4 sol and TiO2 sol. The photocatalytic activities of the new InVO4–TiO2 thin films under visible light irradiation were investigated by the photocatalytic discoloration of methyl orange aqueous
solution. The thin films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM)
and UV–Vis absorption spectroscopy (UV–Vis). The results revealed that the InVO4 doped thin films enhanced the methyl orange degradation rate under visible light irradiation, 3.0 wt% InVO4–TiO2 thin films reaching 80.1% after irradiated for 15 h. 相似文献
9.
Xiaotong Zhang Guowei Zhou Huayong Zhang Cuicui Wu Hongbin Song 《Transition Metal Chemistry》2011,36(2):217-222
Nitrogen and lanthanum co-doped titania photocatalysts were prepared by a modified sol–gel process with urea and lanthanum
nitrate doping precursors and characterized by various techniques including XRD, FTIR, TEM, EDS, and UV–Vis DRS. The average
crystallite size was ca. 12–15 nm as calculated from XRD patterns, and anatase was the dominant crystalline type in the as-prepared
samples. The UV–Vis DRS of the samples revealed significant absorption within the range of 400–500 nm. The optimum composition
of N(0.020)La(0.012)TiO2 exhibited the highest photocatalytic activity for degradation of methyl orange (MO) aqueous solution under simulated sunlight.
The percent degradation of MO was ca. 97% for N(0.020)La(0.012)TiO2 under simulated sunlight irradiation for 9 h. The enhanced photocatalytic activity was ascribed to the synergistic effects
of the nitrogen and lanthanum co-doping. 相似文献
10.
J. Bennaceur R. Mechiakh F. Bousbih M. Jaouadi R. Chtourou 《Journal of Sol-Gel Science and Technology》2012,61(1):69-76
Titanium dioxide doped with iron (III) was prepared by sol–gel Spin Coating method. The phase structures, morphologies, particle
size of the doped TiO2 have been characterized by X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM) and ultraviolet–visible
(UV–Vis) spectrophotometer. The XRD and Raman results show that the 10% Fe3+-doped TiO2 thin films crystallize in anatase phase between 600 and 800 °C, and into the anatase–rutile phase at 1,000 °C, and further
into the rutile phase when the content of Fe3+ increases (20%). The grain size calculated from XRD patterns shows that the crystallinity of the obtained anatase particles
increased from 39.4 to 43.4 nm as the temperature of annealing increase, whereas the size of rutile crystallites increases,
with increasing Fe3+ concentrations from 36.9 to 38.1 nm. The AFM surface morphology results confirmed that the particle size increases by increasing
the annealing temperature and also with an increasing of Fe3+ content. The optical band gap (E
g) of the films was determined by the UV–Vis spectrophotometer. We have found that the optical band gap decreased with an increasing
of annealing temperatures and also with an increasing of Fe3+ content. 相似文献
11.
You J Liu L Zhao W Zhao X Suo Y Wang H Li Y 《Analytical and bioanalytical chemistry》2007,387(8):2705-2718
A simple and sensitive method for evaluating the chemical compositions of protein amino acids, including cystine (Cys)2 and tryptophane (Try) has been developed, based on the use of a sensitive labeling reagent 2-(11H-benzo[α]-carbazol-11-yl) ethyl chloroformate (BCEC–Cl) along with fluorescence detection. The chromophore of the 1,2-benzo-3,4-dihydrocarbazole-ethyl
chloroformate (BCEOC-Cl) molecule was replaced with the 2-(11H-benzo[α]-carbazol-11-yl) ethyl functional group, yielding the sensitive fluorescence molecule BCEC–Cl. The new reagent BCEC–Cl
could then be substituted for labeling reagents commonly used in amino acid derivatization. The BCEC–amino acid derivatives
exhibited very high detection sensitivities, particularly in the cases of (Cys)2 and Try, which cannot be determined using traditional labeling reagents such as 9-fluorenyl methylchloroformate (FMOC-Cl)
and ortho-phthaldialdehyde (OPA). The fluorescence detection intensities for the BCEC derivatives were compared to those obtained when
using FMOC-Cl and BCEOC-Cl as labeling reagents. The ratios I
BCEC/I
BCEOC = 1.17–3.57, I
BCEC/I
FMOC = 1.13–8.21, and UVBCEC/UVBCEOC = 1.67–4.90 (where I is the fluorescence intensity and UV is the ultraviolet absorbance). Derivative separation was optimized on a Hypersil BDS
C18 column. The detection limits calculated from 1.0 pmol injections, at a signal-to-noise ratio of 3, ranged from 7.2 fmol for
Try to 8.4 fmol for (Cys)2. Excellent linear responses were observed, with coefficients of >0.9994. When coupled with high-performance liquid chromatography,
the method established here allowed the development of a highly sensitive and specific method for the quantitative analysis
of trace levels of amino acids including (Cys)2 and Try from bee-collected pollen (bee pollen) samples. 相似文献
12.
Yan Xiong Jing Xu Jian-Wei Wang Ya-Feng Guan 《Analytical and bioanalytical chemistry》2009,394(3):919-923
We have prepared a novel fiber-optic evanescent wave sensor (FEWS) for dissolved oxygen (DO) detection. The sensor fabrication
was based on coating a decladded portion of an optical fiber with a microporous coating, which was prepared from 3,3,3-trifluoropropyltrimethoxysilane
and n-propyltrimethoxysilane. The fluorophores were immobilized in the porous coating and excited by the evanescent wave field
produced on the core surface of the optical fiber. The sensitivity of the sensor was quantified by the ratio of the fluorescence
intensities in pure deoxygenated (I
0) and in pure oxygenated environments (I). Results show that the quenching response of DO is increased with the enhancement of the coating surface hydrophobicity
using the presented hybrid fluorinated ORMOSILs. The calibration curve of I
0/I to [O2] is linear from 0 to 40 ppm and the detection limit is 0.05 ppm (3σ) with a short response time of 15 s for DO detection.
Figure 相似文献
13.
Wagner José Barreto Sonia Regina Giancoli Barreto Waleria Pickina Silva 《Transition Metal Chemistry》2009,34(6):677-681
The reaction between Fe(III) and dopamine in aqueous solution in the presence of Na2S2O3 was followed through UV–Vis spectroscopy, pH and oxy-reduction potential (Eh) measurements. The formation and quick disappearing
of the complex [Fe(III)HL1−]2+, HL1− = monoprotonated dopamine was observed with or without S2O3
2− at pH 3. An unexpected reaction occurs in presence of thiosulfate forming the stable anion complex [Fe(III)(L2−)2]1−, L2− = dopacatecholate (λ = 580 nm) and the auto-increasing of the pH, from 3 to 7. It was proposed that H+ and molecular oxygen are consumed by free radical thiosulfate formed during the reaction. 相似文献
14.
Stela Dimitrova Kostantsa Pavlova Ludmil Lukanov Plamen Zagorchev 《Applied biochemistry and biotechnology》2010,162(3):795-804
The effect of different doses of visible (Vis), ultraviolet-А (UVA), and mixed light (UVA + Vis) upon coenzyme Q10 (CoQ10) and β-carotene synthesis and biomass yield by the Sporobolomyces salmonicolor AL1, Cryptococcus albidus AS55, Cryptococcus laurentii AS56, and C. laurentii AS58 strains isolated from Antarctic samples was investigated. The β-carotene concentration in the red strain biomass increased
by 52% under irradiation with 11 J/cm2 Vis, and the CoQ10 concentration rose by 37% in relation to the control quantity obtained through dark cultivation. Under irradiation with 6 J/cm2 UVA, the S. salmonicolor AL1 strain synthesized 15% more β-carotene; C. albidus AS55, 22%; C. laurentii AS56, 44%; and C. laurentii AS58, 35% in relation to the control quantity. Irradiation with a low UVА + Vis dose significantly stimulated β-carotene biosynthesis
by the strains of the Cryptococcus genus (87%, 138%, and 100%), whereas S. salmonicolor AL1 increased the β-carotene content to a smaller degree (55%). Higher doses of all three irradiation types inhibited β-carotene
accumulation. Vis suppressed CoQ10 biosynthesis in the Cryptococcus strains, whereas UVА and UVА + Vis inhibited it in all four strains. The S. salmonicolor AL1 strain pre-treated with 0.02 J/cm2 UVA synthesized twice as much CoQ10 and β-carotene when cultivated in the presence of Vis light in an 11-J/cm2 dose. 相似文献
15.
Kumar S. Ashok Wang Sea-Fue Yeh Chun-Ting Lu His-Chuan Yang Jen-Chang Chang Yu-Tsern 《Journal of Solid State Electrochemistry》2010,14(11):2129-2135
In this study, stable and homogenous thin films of multiwalled carbon nanotubes (MWCNTs) were obtained on conducting surface
using ciprofloxacin (CF, fluoroquinolone antibiotic) as an effective-dispersing agent. Further, MWCNTs/CF film modified electrodes
(glassy carbon and indium tin oxide-coated glass electrode) are used successfully to study the direct electrochemistry of
proteins. Here, cytochrome C (Cyt-C) was used as a model protein for investigation. A MWCNTs/CF film modified electrode was
used as a biocompatible material for immobilization of Cyt-C from a neutral buffer solution (pH 7.2) using cyclic voltammetry
(CV). Interestingly, Cyt-C retained its native state on the MWCNTs/CF film. The Cyt-C adsorbed MWCNTs/CF film was characterized
by scanning electron microscopy (SEM), UV–visible spectrophotometry (UV-vis) and CV. SEM images showed the evidence for the
adsorption of Cyt-C on the MWCNTs/CF film, and UV–vis spectrum confirmed that Cyt-C was in its native state on MWCNTs/CF film.
Using CV, it was found that the electrochemical signal of Cyt-C was highly stable in the neutral buffer solution and its redox
peak potential was pH dependent. The formal potential (−0.27 V) and electron transfer rate constant (13 ± 1 s−1) were calculated for Cyt-C on MWCNTs/CF film modified electrode. A potential application of the Cyt-C/MWCNTs/CF electrode
as a biosensor to monitor H2O2 has been investigated. The steady-state current response increases linearly with H2O2 concentration from 2 × 10−6 to 7.8 × 10−5 M. The detection limit for determination of H2O2 has been found to be 1.0 × 10−6 M (S/N = 3). Thus, Cyt-C/MWCNTs/CF film modified electrode can be used as a biosensing material for sensor applications. 相似文献
16.
A Multilayer Film for Bifunctional Electrocatalyst and Electrochemical Sensor Based on Polyoxometalate and Tris(1,10-Phenanthroline)Ruthenium 总被引:1,自引:0,他引:1
The multilayer films containing tris(1,10-phenanthroline) ruthenium(II) Ru(phen)3Cl2 (abbr. Ru(phen)3, phen = 1,10-phenanthroline) and polyoxometalate [P2W18O62]6− (abbr. P2W18) through a layer-by-layer (LBL) process were fabricated. UV–vis absorption spectra showed that the subsequent growth of the
multilayer film was regular and highly reproducible from layer to layer. X-ray photoelectron spectra (XPS) confirmed the incorporation
of Ru(phen)3 and P2W18 into the film. The result of atomic force microscopy (AFM) revealed a relatively uniform surface morphology of the multilayer
film. The multilayer film exhibited remarkable electrocatalytic activities toward the reduction of
\textIO3 - {\text{IO}}_{3}^{ - } and the oxidation to l-cysteine. The value of I
pc was as a function with the concentration of iodate and l-cysteine, which indicated that the film can be a candidate for bifunctional electrocatalyst and electrochemical sensor. 相似文献
17.
Masoud Salavati-Niasari Fatemeh Davar Masoud Farhadi 《Journal of Sol-Gel Science and Technology》2009,51(1):48-52
Nanocrystalline Copper aluminate (CuAl2O4) was prepared by sol–gel technique using aluminum nitrate, copper nitrate, diethylene glycol monoethyl ether and citric acid
were used as precursor materials. This method starts from of the precursor complex, and involves formation of homogeneous
solid intermediates, reducing atomic diffusion processes during thermal treatment. The formation of pure crystallized CuAl2O4 nanocrystals occurred when the precursor was heat-treated at 600 °C in air for 2 h. The stages of the formation of CuAl2O4, as well as the characterization of the resulting compounds were done using thermo–gravimetric analysis, X-ray diffraction,
scanning electron microscopy and Fourier transform infrared spectroscopy. The products were analyzed by transmission electron
microscopy and ultraviolet–visible (UV–Vis) spectroscopy to be round, about 17–26 nm in size and E
g = 2.10 eV. 相似文献
18.
Jason C. Sanchez Antonio G. DiPasquale Anthony A. Mrse William C. Trogler 《Analytical and bioanalytical chemistry》2009,395(2):387-392
The high sensitivity of silole- and silafluorene-containing polymers for detecting organic nitro, nitrate, and nitramine explosives
cannot be solely attributed to favorable analyte–polymer hydrophobic interactions and amplified fluorescence quenching due
to delocalization along the polymer chain. The Lewis acidity of silicon in conjugated poly(silafluorene-vinylene)s is shown
to be important. This was established by examining the 29Si NMR chemical shifts (Δ) for the model trimer fragment of the polymer CH3–silafluorene–(trans-C2H2)–silafluorene–(trans-C2H2)–silafluorene–CH3. The peripheral and central silicon resonances are up-field from a TMS reference at −9.50 and −18.9 ppm, respectively. Both
resonances shift down-field in the presence of donor analytes and the observed shifts (0 to 1 ppm) correlate with the basicity
of a variety of added Lewis bases, including TNT. The most basic analyte studied was acetonitrile and an association constant
(K
a) of 0.12 M−1 was calculated its binding to the peripheral silicon centers using the Scatchard method. Spin-lattice relaxation times (T
1) of 5.86(3) and 4.83(4) s were measured for the methyl protons of acetonitrile in benzene-d
6 at 20 °C in the absence and presence of the silafluorene trimer, respectively. The significant change in T
1 values further supports a binding event between acetonitrile and the silafluorene trimer. These studies as well as significant
changes and shifts observed in the characteristic UV–Vis absorption of the silafluorene group support an important role for
the Lewis acid character of Si in polymer sensors that incorporate strained silacycles. The nitro groups of high explosives
may act as weak Lewis-base donors to silacycles. This provides a donor–acceptor interaction that may be crucial for orienting
the explosive analyte in the polymer film to provide an efficient pathway for inner-sphere electron transfer during the electron-transfer
quenching process.
Figure
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Atanu Jana Chinmoy Bhattacharya Subrata Sinha Jayati Datta 《Journal of Solid State Electrochemistry》2009,13(9):1339-1350
Bismuth sulfide (Bi2S3) thin films were electrodeposited from non-aqueous dimethyl sulfoxide medium containing Bi(NO3)3 and thiourea as the precursor salts, triethanol amine as the complexing agent, and TritonX-100 as the surface active agent.
The prepared films were subjected to rigorous experimentation in order to validate their potential candidature for solar cells.
The films exhibited band gap energy of ∼1.3 eV and resistivity of the order of 2 × 106 Ω cm at room temperature as was obtained from UV–Vis spectroscopy and four-probe measurements, respectively. Scanning electron
microscopy, transmission electron microscopy, X-ray diffraction, and energy dispersive analysis of X-ray were employed to
reveal the morphology, structure, and chemical composition of the film matrix. The Bi2S3 films were found to be non-decomposable up to the temperature of 1,000 °C with the help of thermogravimetry–differential
thermal analysis. The Nyquist and Mott–Schottky plots derived from electrochemical impedance spectroscopy measurements provided
important information regarding electrical and semiconducting properties of the films. The n-type film with a donor density of the order of ∼1023 m−3 displayed reasonable photoactivity under illumination and is recommended as a promising candidate for potential photoelectrochemical
applications. 相似文献
20.
Cai Jin-Hua Ye Yuan-Jian Huang Jin-Wang Yu Han-Cheng Ji Liang-Nian 《Journal of Sol-Gel Science and Technology》2012,62(3):432-440
Three types of silica gel supported titanium dioxide particles immobilizing Zn(II) carboxylphenyl porphyrins appending p-CH3, p-H and p-Cl phenyl substituents (designated as ZnMP–TiO2–SiO2, ZnPP–TiO2–SiO2 and ZnCP–TiO2–SiO2, respectively) have been synthesized and characterized using SEM, XRD, IR, AFS, DRS, UV–Vis, XPS and TG. The photodegradation
of α-terpinene in aqueous suspension was used to determine the photocatalytic activity of TiO2–SiO2 samples which had been impregnated with Zn(II) porphyrins, as sensitizers. The experimental results confirmed that the photocatalytic
activitys of these composites are much higher than those of the nonmodified TiO2–SiO2 under visible light irradiation and follow the order of ZnMP–TiO2–SiO2 > ZnPP–TiO2–SiO2 > ZnCP–TiO2–SiO2. 相似文献