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1.
The possibility for preparing Co 3MnO x· nH 2O and LiCo 3MnO x· nH 2O nanolayers by successive ionic layer deposition was examined. The resulting layers were studied by X-ray photoelectron spectroscopy, UV-Vis diffuse reflection spectroscopy, Fourier transmission IR spectroscopy, atomic absorption spectroscopy, ellipsometry, and X-ray powder diffraction. 相似文献
2.
A novel SrTiO 3/BiPO 4 heterostructure with different amounts of SrTiO 3 have been successfully prepared through the hydrothermal process. The photocatalysts were characterized by X-ray powder diffraction, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic performance was evaluated by degrading the methylene blue dye solution under UV light. Results showed that the samples displayed excellent photocatalytic degradation efficiency due to the highly efficient suppression of the recombination of electron–hole pairs. A possible mechanism of SrTiO 3/BiPO 4 heterojunctions was discussed. The research indicated that the as-prepared SrTiO 3/BiPO 4 heterogeneous photocatalyst can be used as an effective material for degrading industrial organic wastewater. 相似文献
3.
Efficient exfoliation and downsizing of Sb 2S 3 and Bi 2S 3 layered compounds by using scalable bipolar electrochemistry on their suspensions in aqueous media are here demonstrated. The resulting samples were characterized in detail by transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy; their electrochemistry toward hydrogen evolution was also investigated. Hydrogen evolution ability of exfoliated Sb 2S 3 and Bi 2S 3 was investigated and compared to the bulk counterparts. 相似文献
4.
A simple, rapid, one-step synthesis way of pure iron oxide nanoparticles: magnetite (Fe 3O 4), maghemite (γ-Fe 2O 3) and hematite (α-Fe 2O 3) was investigated. Nanoparticles were prepared by microwave synthesis, from ethanol/water solutions of chloride salts of
iron (FeCl 2 and FeCl 3) in the presence of sodium hydroxide NaOH. X-ray powder diffraction (XRD), Transmission Electron Microscopy (TEM), Fourier
transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to characterize these nanoparticles. 相似文献
5.
Triethylamine borane (TEAB) and He, N 2 or NH 3 were applied as additional reaction gases in the production of BC xN y layers by low-pressure chemical vapor deposition (LPCVD). These layers were deposited on Si(100) wafers and characterized
chemically by X-ray photoelectron spectroscopy (XPS) and synchrotron radiation-based total-reflection X-ray fluorescence analysis
combined with near-edge X-ray absorption fine-structure spectroscopy (TXRF-NEXAFS). The composition of the material produced
without NH 3 was found to be dominated by B–C bonds with the stoichiometric formula B 2C 3N. B–N bonds with the formula B 2CN 3 were preferred when NH 3 was added. A first attempt was made to compare the results obtained by applying trimethylamine borane and TEAB as single-source
precursors. 相似文献
6.
采用X射线粉末衍射(XRD)、X射线荧光光谱(XRF)和扫描电子显微镜-能谱(SEM-EDS)等测试技术对西安西曹M16唐墓出土的2尊唐代彩绘陶俑颜料进行了化学组成分析。结果表明,陶俑中含有丰富的无机颜料,其中红色颜料的显色成分为铅丹(Pb 3O 4);白色颜料的显色成分为铅白(PbCO 3)和石灰石(CaCO 3);粉色颜料的主要显色成分为铅丹和铅白的混合物;青色颜料为铜绿(Cu 2(OH) 2CO 3)和青石(Cu 3(OH) 2(CO 3) 2)混合物。 相似文献
7.
In this research study, WO 3/NaNbO 3-coupled photocatalysts were synthesized at three WO 3 mass ratios (15, 85, and 95 wt%) and characterized. These composites were characterized via X-ray powder diffraction, N 2 physisorption, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and photoluminescence techniques. For comparison, bare WO 3 and NaNbO 3 were also synthesized and characterized. 2,4-Dichlorophenoxyacetic acid (2,4-D) was degraded under visible light to evaluate its photocatalytic performance. The WO 3 (95 wt%)/NaNbO 3 composite showed higher photocatalytic activity than pure WO 3 and NaNbO 3 and even than the 15 and 85 wt% coupled materials; thus, the combination with the highest ratio of WO 3 with respect to NaNbO 3 showed increased photocatalytic activity compared with the bare materials. 相似文献
8.
The Cu 3Se 2 nanofilms were synthesized with underpotential deposition based electrochemical codeposition technique for the first time in the literature. The electrochemical behaviors of copper and selenium were investigated in 0.1 M H 2SO 4 on Au electrode. The effects of concentration and scan rate on the electrochemical behavior of selenium were studied. The electrochemical behaviors in underpotential deposition and bulk regions of the Cu-Se system were investigated in acidic solution by cyclic voltammetry and electrolysis techniques. X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, Raman spectroscopy, and ultraviolet and visible absorption spectroscopy techniques were used for characterization of synthesized films. According to the X-ray photoelectron spectroscopy spectrum, Cu/Se ratio was determined to be approximately 3/2. Copper selenide nanofilms are two phases and polycrystalline according to X-ray diffraction. The films mainly formed tetragonal Cu 3Se 2 ( umangite mineral structure) structure and the particle size was approximately 45.95 nm. Scanning electron microscopy images showed that Cu 3Se 2 nanofilms consisted of uniform, nano-sizes and two-dimensional. It was found through AFM that the surface roughness of the film was 6.173 nm, with a mean particle size of around 50 nm. Depending on the deposition time, the band gaps of the Cu 3Se 2 films were in the range of 2.86–3.20 eV. Three characteristic vibrational modes belonging to Cu 3Se 2 nanofilms were recorded in the Raman spectrum. 相似文献
9.
Technetium tetrachloride and β-TcCl 3, synthesized from the reaction of Tc metal and Cl 2(g) in sealed tubes, were characterized by X-ray absorption fine structure spectroscopy. Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements are in good agreement with the X-ray diffraction structures of the two compounds. For TcCl 4, the absorbing Tc atom is surrounded by Cl atoms at 2.34(2) Å and Tc atoms at 3.66(4) Å. For β-TcCl 3, the absorbing Tc atom is surrounded by Cl atoms at 2.40(2) Å and Tc atoms at 2.81(3), 3.66(4) and 5.71(6) Å. EXAFS spectroscopy indicates that the TcCl 4 and β-TcCl 3 samples obtained by sealed tube reactions are single phase. The X-ray absorption near edge structure spectra of TcCl 4 and β-TcCl 3 were recorded; the positions of the Tc K-edges of β-TcCl 3 (21,050.5 eV) and TcCl 4 (21,053.0 eV) are compared to the ones measured for α-TcCl 3 (21,051.0 eV) and TcCl 2 (21,048.8 eV). A correlation between the positions of the Tc K-edges and the oxidation state of the Tc atom in technetium binary chlorides was determined. 相似文献
10.
The nanosized xerogel of titanium dioxide (TiO 2) and manganese oxides (MnO 2, Mn 2O 3, Mn 3O 4) was prepared by the sol-gel method using manganese chloride (MnCl 2·4H 2O) and titanium isopropoxide (Ti(O-iPr) 4) as precursors in cetyltrimethylammonium bromide (CTAB)/ ethanol/H 2O/HCl micelle solutions, following the calcinations of the produced powders at difference temperatures. The nanostructure
and phase composition of these nanoparticles were characterized with X-ray powder diffraction (XRD), transmission electron
microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The spectroscopic
characterizations of these nanoparticles were also done with UV-Vis spectroscopy and laser Raman spectroscopy (LRS). XRD patterns
show that the pyrophanite MnTiO 3 phase was formed at the calcinations temperature of 900°C. The TEM images show that the nanoparticles are almost spherical
or slight ellipose and the sizes are 50 nm on average. The UV-Vis spectra show that the nanosized MnTiO 3 have significant absorption bands in the visible region. There are new absorption peaks of MnTiO 3 nanoparticles in LRS compared with the pure TiO 2 powder. 相似文献
11.
A one-step green-chemistry method was applied to prepare sulfur/reduced graphene oxide (S/RGO). The synthesized S/RGO was modified by 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) and Fe 3O 4 nanoparticles to form TCPP–Fe 3O 4@S/RGO. The prepared composites were investigated by X-ray diffraction (XRD) analysis, Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray (EDX) mapping, and transmission electron microscopy (TEM) and scanning electron microscopy (SEM) imaging. Diffuse reflectance spectroscopy (DRS) was used to determine the photocatalytic ability of S/RGO and TCPP–Fe 3O 4@S/RGO. In addition, photocatalytic degradation of a hazardous dye (methylene blue) by the TCPP–Fe 3O 4@S/RGO composite under visible-light irradiation is reported. The results demonstrate synthesis of TCPP–Fe 3O 4@S/RGO by an environmentally friendly method with excellent degradation effect. 相似文献
12.
The highly ordered LaNiO 3 nanowires of the rare-earth perovskite-type composite oxide were controlled synthesized within a porous anodic aluminum oxide (AAO) template by means of sol-gel method using nitrate as raw materials and citric acid as chelating agent. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the obtained LaNiO 3 nanowires had a uniform length and diameter, which were determined by the thickness and the pore diameter of the applied AAO template. The results of X-ray diffraction (XRD) and the selected-area electron diffraction (SAED) indicated that the LaNiO 3 nanowires were perovskite-type crystalline structures. Furthermore, X-ray photoelectron spectroscopy (XPS) and the energy dispersive X-ray (EDX) spectroscopy demonstrated that the stoichiometric LaNiO 3 was formed. 相似文献
13.
Rhombus-like SmCO 3OH microplates with the edge lengths ranging from 5 μm to 10 μm and the thickness about 1.5 μm were synthesized through a simple hydrothermal method using urea as the precipitance. The structure and properties of the rhombus-like SmCO 3OH microplates were characterized by X-ray diffraction, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The optical property of the rhombus-like SmCO 3OH microplates doped with Eu 3+ was investigated by photoluminescence. A broad and strong emission band at 677 nm was obtained, which can be contributed to producing light conversion film. 相似文献
14.
YFeO 3 was prepared by coprecipitation method and citric acid method, and TiO 2/YFeO 3 heterosystem photocatalysts were synthesized by loading TiO 2 sol on the surface of YFeO 3via sol-gel method. Their photocatalytic activities were evaluated by the decomposition of gaseous benzene under UV light illumination. The prepared photocatalysts were characterized by nitrogen adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Vis diffuse reflectance spectroscopy. Results revealed that the heterosystem photocatalysts prepared by coprecipitation method showed higher activity, and the maximum conversion of benzene could reach 44.7% within 180 min. The YFeO 3 samples prepared from coprecipitation method and citric acid method were absolutely in orthorhombic phase. The deposited titania was dispersed on the surface of carrier and a certain interaction existed between TiO 2 and YFeO 3. The two heterosystems photocatalysts had narrow band-gap energies. 相似文献
15.
通过在三聚氰胺热分解过程中加入NaHCO 3制备出具有氮缺陷的石墨相氮化碳(g-C 3N 4),利用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、N 2吸附-脱附、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-vis DRS)和固体荧光光谱(PL)等方法对其进行表征,并在可见光(λ> 420nm)照射下,以水相中罗丹明B(RhB)的降解为模型反应,研究了该氮缺陷g-C 3N 4对有机污染物降解的光催化活性。结果表明,引入氮缺陷可以提高g-C 3N 4对可见光的吸收以及电子-空穴对的分离效率,进而提高g-C 3N 4的可见光催化活性。催化剂CNK0.005、CNK0.01和CNK0.05在30min内对RhB的降解率分别为79.8%、100.0%和87.6%;而在相同条件下,没有氮缺陷的g-C 3N 4对RhB的降解率仅为59.8%。 相似文献
16.
Organic dyes are used in many industries, e.g., textile, cosmetics and food. Hence, contamination of organic dyes to water sources is a critical issue. To reduce water pollution by organic dyes, we propose a paper-like adsorbent with a practical and economical production procedure. Subsequently, a flexible adsorbent was produced using a one-step approach by vacuum filtration of graphene oxide (GO) and iron oxide nanoparticles (Fe3O4-NPs) containing dispersion through a membrane and quoted as GO/Fe3O4 paper. For comparison, GO paper was also prepared using the same procedure. Both papers were characterized using UV–VIS absorption spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, electron diffraction X-ray analysis, X-ray photoelectron spectroscopy, and powder X-ray diffraction techniques. At the steady-state conditions, GO/Fe3O4 and GO papers were performed as adsorbent for cationic dyes of methylene blue, neutral red, and anionic dyes of methyl orange and fluorescein. In general, the removal efficiency of GO/Fe3O4 paper was higher than that of GO paper for adsorption of all dyes and this adsorbent revealed satisfactory adsorption properties for cationic dyes when compared to anionic dyes. 相似文献
17.
A series of Cr-based metal–organic framework MIL-101-SO 3H bearing sulfonic acid functional groups were utilized for the immobilization of catalytically active copper species via a post-synthetic metalation method. The novel materials were fully characterized by scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), the Brunauer–Emmett–Teller method, and thermogravimetric analysis. XPS and the EDX element map both suggested that Cu 2+ is coordinately bonded to the MIL-101-SO 3H, which forms the MIL-101-SO 3@Cu structure. The obtained copper-doped MIL-101-SO 3@Cu-1, MIL-101-SO 3@Cu-2, and MIL-101-SO 3@Cu-3 catalysts were utilized in the selective oxidation of alcohols and epoxidation of olefins using molecular oxygen as an oxidant. Catalytic aerobic oxidation optimization showed that MIL-101-SO 3@Cu-1 is the optimal catalyst and it can be reused ten times without compromising the yield and selectivity. 相似文献
18.
(Me 3Si) 2SiMe 2, (Me 3Si) 3SiMe and (Me 3Si) 4Si were used as precursors for the deposition of polycrystalline β-SiC thin films on silicon substrates at 1000–1200°C in a low-pressure hot-wall chemical vapor deposition reactor. The thin films were analyzed by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. 相似文献
19.
A series of alkaline uranyl carbonates, M[UO 2(CO 3) 3]· nH 2O ( M=Mg 2, Ca 2, Sr 2, Ba 2, Na 2Ca, and CaMg) was synthesized and characterized by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS) after nitric acid digestion, X-ray powder diffraction (XRD), and thermal analysis (TGA/DTA). The molecular structure of these compounds was characterized by extended X-ray absorption fine-structure (EXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS). Crystalline Ba 2[UO 2(CO 3) 3]·6H 2O was obtained for the first time. The EXAFS analysis showed that this compound consists of (UO 2)(CO 3) 3 clusters similar to the other alkaline earth uranyl carbonates. The average U-Ba distance is 3.90±0.02 Å.Fluorescence wavelengths and life times were measured using time-resolved laser-induced fluorescence spectroscopy (TRLFS). The U-O bond distances determined by EXAFS, TRLFS, XPS, and Raman spectroscopy agree within the experimental uncertainties. The spectroscopic signatures observed could be useful for identifying uranyl carbonate species adsorbed on mineral surfaces. 相似文献
20.
采用硝酸锌、五氧化二钒和氢氧化钠作为反应物,通过一个简单的CTAB辅助的水热方法制备了Zn 3(OH) 2V 2O 7·2H 2O纳米片。运用XRD,ICP-AES,FTIR,HRTEM,EDS,FE-SEM对产物的晶相和形貌进行了表征。结果表明CTAB在控制产物的形貌、尺寸分布和自组装过程中起着关键作用。同时我们研究了产物的晶体生长行为和自组装过程。 相似文献
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