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1.
生物分子辅助溶剂热合成硫化锑纳米棒   总被引:1,自引:1,他引:0  
以SbCl3和L-胱氨酸为反应原料,采用溶剂热法在170℃反应12h,制得硫化锑(Sb2S3)纳米棒.X射线衍射(XRD)、能量分散光谱(EDS)和X射线光电子能谱(XPS)研究表明所得产物为典型的Sb2S3正交结构.场发射扫描电子显微镜(FESEM)和透射电子显微镜(TEM)研究显示,Sb2S3纳米棒长为3~6μm,平均直径约为150nm.讨论了不同反应时间对Sb2S3的形成及其形貌的影响,并根据实验结果对所合成的一维纳米棒可能的形成机理进行了简单的探讨.  相似文献   

2.
The effect of antimony doping of tin dioxide at Sb/Sn = 0.2–2.5 on the physical properties and structure of air-dry samples of hydrous tin dioxide, SnO2 ? nH2O (HTD), was studied by IR and Raman spectroscopy, powder X-ray diffraction, impedance measurements, TGA, and electron microscopy. The doped materials retained the structure of undoped HTD materials if the Sb/Sn ratio did not exceed the threshold value of 1.0. When Sb/Sn > 1, crystalline antimony oxide admixture appeared. The data of IR spectroscopy attested to the presence of two types of water in HTD-Sb, namely, physisorbed and chemisorbed water. The major part of water of the former type can be removed by evacuation at room temperature. Chemisorption occurs upon coordination of water molecules by metal ions through the formation of metal–oxygen bonds. Water molecules of the latter type are retained in evacuated samples at room temperature and on heating above the boiling point of liquid water. By impedance spectroscopy, HTD-Sb samples were shown to possess fairly high proton conductivity at high humidity; however, the conductivity decreased by two orders of magnitude after partial removal of water molecules of the former type. This attests to the destruction of the loosely bound hydrogen bond network, across which proton transfer takes place. It was also found that under conditions of constant humidity, the proton conductivity successively decreases with increasing antimony concentration. This is attributable to the fact that Sb(III) ions polarize the local environment to a lesser extent than Sn(IV) ions.  相似文献   

3.
Pt hydrosols have been synthesized by dispersing a pure Pt wire in a NaOH solution with square wave potential (SWP) or alternating voltage (AV). The rearrangements of superfacial Pt atoms by repeated and fast electro-redox under the potential perturbations (PPs), coupling with the impetus of concurrent hydrogen gas, account for this novel dispersion of bulk Pt. Using this strategy we are able to realize the green and facile synthesis of clean Pt nanoparticles (NPs) requiring no any precursor ions and reducers in aqueous solution under mild conditions. Moreover, the dispersion of bulk Pt has also been carried out by paired electrolysis with two Pt wires. The as-prepared Pt NPs were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM) and powder X-ray diffraction (XRD). The Pt NPs exhibit high electrocatalytic activity toward the ethanol electrooxidation and weak surface-enhanced Raman scattering (SERS) signals for adsorbed pyridine.  相似文献   

4.
张兰  尉继英  赵璇  李福志  江锋 《物理化学学报》2001,30(10):1923-1931
90Sr 是核电站放射性废液中需要重点去除的核素之一,水合锑氧化物Sb2O5·mH2O可以在酸性条件下选择性吸附脱除90Sr. 本文在以醇为溶剂的无水体系中,以化学性能较稳定且毒性低的SbCl3为原料,以紫外线照射辅助双氧水氧化及控制水解两步法制备出自掺杂型锑氧化物Sb(Ⅲ)/Sb2O5. 文中采用X射线光电子能谱(XPS)、X射线衍射(XRD)和傅里叶变换红外(FTIR)光谱对材料结构进行结构表征,并采用批量实验方法研究不同Sb(Ⅲ)/Sb(total)比例与Sr(Ⅱ)吸附性能的相关性,以及溶液pH 值对Sr(Ⅱ)吸附性能的影响. 实验结果表明:Sb(Ⅲ)可在较大的比例范围内共存于立方烧绿石型Sb2O5晶格内,形成良好的固溶体Sb(Ⅲ)/Sb2O5;制备过程中通过控制醇溶剂的类型、氧化剂的添加方式以及两步反应温度,可以获得具有不同氧化率,即不同Sb(Ⅲ)/Sb(total)比例的Sb(Ⅲ)/Sb2O5材料;其中Sb(Ⅲ)/Sb(total)比例为49.8%的锑氧化物材料吸附性能最好,在纯水体系下对Sr(Ⅱ)的分配系数为6.6×107 mL·g-1,在pH=3-13 范围内对Sr(Ⅱ)具有良好的吸附性能,并且在本文实验条件下,Sr(Ⅱ)在锑氧化物材料上的吸附更好地符合Langmuir吸附模型.  相似文献   

5.
The antimony-121 M?ssbauer spectra of Eu10Mn6Sb13 have been measured between 2 and 295 K. Although the Zintl formalism indicates that the nine crystallographically distinct antimony sites in Eu10Mn6Sb13 should have formal valence states of -2, -1, 0, and +1, the M?ssbauer spectral isomer shifts reveal that the valence states of the different sites are all quite similar and correspond to an average electronic configuration for antimony of 5s(1.7)5p(4.0). This configuration corresponds to an excess of negative charge on the antimony of 0.7 or an average valence of -0.7, a valence which is rather consistent with the average antimony valence of -0.61 obtained from the Zintl formalism for the nine antimony sites in Eu10Mn6Sb13. The spectra obtained between 90 and 295 K are more consistent with the absence rather than the presence of any transferred magnetic hyperfine field at the antimony. In contrast, the spectra obtained at 2 and 5 K reveal the presence of an average transferred magnetic hyperfine field of ca. 8 T, a field that arises from the ferromagnetic ordering of the near-neighbor manganese(II) ions.  相似文献   

6.
The speciation of inorganic Sb(III) and Sb(V) ions in aqueous solution was studied. The adsorption behavior of Sb(III) and Sb(V) ions were investigated as iodo and ammonium pyrollidine dithiocarbamate (APDC) complexes on a column filled with Amberlite XAD-8 resin. Sb(III) and Sb(V) ions were recovered quantitatively and simultaneously from a solution containing 0.8 M NaI and 0.2 M H2SO4 by the XAD-8 column. Sb(III) ions were also adsorbed quantitatively as an APDC complex, but the recovery of the Sb(V)-APDC complex was found to be <10% at pH 5. According to these data, the concentrations of total antimony as Sb(III)+Sb(V) ions and Sb(III) ion were determined with XAD-8/NaI+H2SO4 and XAD-8/APDC systems, respectively. The Sb(V) ion concentration was calculated by subtracting the Sb(III) concentration found with XAD-8/APDC system from the total antimony concentration found with XAD-8/NaI+H2SO4 system. The developed method was applied to determine Sb(III) and Sb(V) ions in samples of artificial seawater and wastewater.  相似文献   

7.
SiO2/TiO2/graphite (STG) electrically conducting material, prepared by the sol–gel processing method, was used as substrate base for the chemical immobilization of Sb(V) by formation of the Ti–O–Sb linkage. The surface modified material, STGSb, was characterized by X-ray photoelectron spectroscopy and scanning electronic microscopy coupled to energy dispersive spectroscopy. The results showed the Sb(V) homogeneously dispersed on the STG matrix surface, with no phase segregation or isolated pure oxide domains. An electrode prepared with the STGSb material was used to adsorb the electroactive cationic dye meldola blue. The modified electrode, STGSb/MB, presented good performance toward electrocatalytic oxidation of the coenzyme β-NADH (nicotinamide adenine dinucleotide). The electrode was shown to be very stable and allowed the electrochemical detection of NADH at low electrode potential (−0.14 V), which is an interesting feature of the system since in this potential range it is possible to minimize surface fouling and electrode passivation. The support material (STGSb) has proven to have great potential to be applied in the construction of various new electrochemical sensors based on cationic dyes presenting redox properties.  相似文献   

8.
This paper studies the antimony spreading and segregation that occurred along with the oxidation and solid-state reactions in the Fe2O3-Sb2O3 system. XRD, SEM, TG-DSC and particularly XPS were employed for characterizations. Sb2O4 and FeSbO4 are the only new phases detected. The formation of FeSbO4 is a more exothermic but slower reaction than oxidation of Sb2O3. A mechanical grinding of Sb2O3 and Fe2O3 leads to a significant dispersion of Sb2O3 possibly because of its low hardness. Dispersion of reference Sb2O4 in this way is negligible. During the heating of a mixture of Sb2O3 and Fe2O3 with an atomic ratio of Sb/Fe = 0.5 at 200-1000 degrees C in ambient air, the thermal spreading of Sb2O3 onto Fe2O3 increases with increasing temperature until Sb2O3 is oxidized into Sb2O4. The surface atomic ratio of Sb/Fe measured by XPS, R(Sb/Fe), reaches a maximum around 400 degrees C. The complete oxidation of Sb2O3 leads to a decrease in R(Sb/Fe) because of poorer dispersibility of Sb2O4. The formation of FeSbO4 starting at ca. 800 degrees C causes a further decrease in R(Sb/Fe), but the R(Sb/Fe) is still 3.2 times the nominal bulk Sb/Fe ratio when the Sb2O4 is completely transformed into FeSbO4.  相似文献   

9.
 Antimony nanocrystals were formed in thin SiO2 films using low-energy ion implantation of Sb followed by annealing. Using Fourier transform laser microprobe mass spectrometry (FT LMMS), we observed for the first time the presence of antimony oxide in the intermediate phase (as-implanted layer of Sb) by means of signals referring to the intact Sb2O3 molecules. Only SbO+ fragments, but no adduct ions of Sb2O3 could be detected in annealed samples. The size and the distribution of the nanocrystals formed around the initial depth of implantation were studied in the as-implanted samples by high-resolution electron microscopy (HREM). The crystalline structure of these nanocrystals was also studied and the presence of antimony trioxide Sb2O3 in the form of valentinite was proven. After the annealing step, the implanted material had spread into a wider band. The method introduced here, based on combining TEM (transmission electron microscopy) and FT LMMS results, offers the possibility of studying the evolution of the phases in Sb nanocrystal formation.  相似文献   

10.
A simple, rapid and selective electrochemical method is proposed as a novel and powerful analytical technique for the solid phase determination of less than 4% antimony in lead-antimony alloys without any separation and chemical pretreatment. The proposed method is based on the surface antimony oxidation of Pb/Sb alloy to Sb(III) at the thin oxide layer of PbSO4/PbO that is formed by oxidation of Pb and using linear sweep voltammetric (LSV) technique. Determination was carried out in concentrate H2SO4 solution. The influence of reagent concentration and variable parameters was studied. Antimony of Pb/Sb alloys can be determined in the range of 0.0056–4.00% with a detection limit of 0.0045% and maximum relative standard deviation of 4.26%. This method was applied for the determination of Sb in lead/acid battery grids satisfactory.  相似文献   

11.
张兰  尉继英  赵璇  李福志  江锋 《物理化学学报》2014,30(10):1923-1931
90Sr是核电站放射性废液中需要重点去除的核素之一,水合锑氧化物Sb2O5·mH2O可以在酸性条件下选择性吸附脱除90Sr.本文在以醇为溶剂的无水体系中,以化学性能较稳定且毒性低的SbCl3为原料,以紫外线照射辅助双氧水氧化及控制水解两步法制备出自掺杂型锑氧化物Sb(Ⅲ)/Sb2O5.文中采用X射线光电子能谱(XPS)、X射线衍射(XRD)和傅里叶变换红外(FTIR)光谱对材料结构进行结构表征,并采用批量实验方法研究不同Sb(Ⅲ)/Sb(total)比例与Sr(Ⅱ)吸附性能的相关性,以及溶液pH值对Sr(Ⅱ)吸附性能的影响.实验结果表明:Sb(Ⅲ)可在较大的比例范围内共存于立方烧绿石型Sb2O5晶格内,形成良好的固溶体Sb(Ⅲ)/Sb2O5;制备过程中通过控制醇溶剂的类型、氧化剂的添加方式以及两步反应温度,可以获得具有不同氧化率,即不同Sb(Ⅲ)/Sb(total)比例的Sb(Ⅲ)/Sb2O5材料;其中Sb(Ⅲ)/Sb(total)比例为49.8%的锑氧化物材料吸附性能最好,在纯水体系下对Sr(Ⅱ)的分配系数为6.6×107mL·g-1,在pH=3-13范围内对Sr(Ⅱ)具有良好的吸附性能,并且在本文实验条件下,Sr(Ⅱ)在锑氧化物材料上的吸附更好地符合Langmuir吸附模型.  相似文献   

12.
The solid-state reactions in the system Cu—Sb—O were investigated by thermogravimetry and X-ray diffraction. Equimolar mixtures of CuO and Sb2O3 form Cu(II)Sb2O6 when slowly heated in air up to 1000°C. The firt step in this reaction is the oxidation of Sb2O3 to Sb2O4 at 380–500°C, followed by further oxidation of Sb2O4 and the formation of CuSb2O6 at 500–1000°C. Thermal decomposition of CuSb2O6 in a flowing nitrogen atmosphere occurs in three stages; the first, with an activation energy of 356 kJ mole?1, results in the formation of a new copper(I) antimony oxide, with a composition of Cu4SbO4.5, as determined by atomic absorption analysis and X-ray fluoresecence. Confirmation of predominantly monovalent copper and pentavalent antimony in the new compound was by ESR and ESCA, respectively. Two forms of Cu4SbO4.5 have been distinguished; one of these (form II) has a structure of lower symmetry, and decomposes when heated in air at 600°C to a mixture of CuO and another new copper antimony oxide, as yet uncharacterized. On further heating to 1100°C in air, Cu4SbO4.5 (form I) gradually reforms. Details of these reactions are summarized and X-ray powder data presented for Cu4SbO4.5.  相似文献   

13.
We report a simple solution route to large-scale synthesis of uniform, single-crystalline, and well-faceted orthorhombic antimony trioxide (Sb(2)O(3)) nanowires with rectangular cross sections by direct air oxidation of bulk metal antimony (Sb) in a mixed solution made of ethylenediamine (EDA) and deionized water (DIW). The as-synthesized products were analyzed by range of methods, such as XRD, SEM, EDX, TEM, SAED, HRTEM, FTIR, Raman, UV-vis absorption, and photoluminescence (PL) spectra. The as-synthesized Sb(2)O(3) nanowires with rectangular cross sections are usually hundreds of micrometers in length, typically 80-100 nm in width, and 60-80 nm in thickness. The novel room temperature photoluminescence properties of Sb(2)O(3) nanowires with rectangular cross sections displayed a significant UV luminescence with a strong emission band at 374 nm, which was reported for the first time, indicating the as-synthesized products with an optical band gap E(g) = 3.3 eV. It is expected that as-synthesized Sb(2)O(3) nanowires would be a new member of functional materials and used in the manufacture of advanced nanodevices.  相似文献   

14.
Reaction of antimony, selenium, and selenium(IV) chloride in the Lewis acidic ionic liquid [BMIM]Cl/AlCl3 (BMIM: 1‐n‐butyl‐3‐methylimidazolium) at room temperature yielded air‐sensitive black block‐shaped crystals of [Sb10Se10][AlCl4]2. The triclinic unit cell (space group ${P\bar 1}Reaction of antimony, selenium, and selenium(IV) chloride in the Lewis acidic ionic liquid [BMIM]Cl/AlCl(3) (BMIM: 1-n-butyl-3-methylimidazolium) at room temperature yielded air-sensitive black block-shaped crystals of [Sb(10)Se(10)][AlCl(4)](2). The triclinic unit cell (space group P1, a=947.85(2), b=957.79(2), c=1166.31(3)?pm; α=103.622(1), β=110.318(1), γ=99.868(1)°; Z=1) contains the first mixed antimony/selenium polycation, [Sb(10)Se(10)](2+). The centrosymmetric polycyclic cation consists of two realgar-like [Sb(4)Se(4)] cages, which are connected through positively charged, three-bonded selenium atoms with a central [Sb(2)Se(2)] ring. Quantum chemical calculations predict semiconducting behavior of the compound and indicate primarily covalent bonding with varying ionic contribution within the [Sb(10)Se(10)](2+) polycation, while the interactions between the polycation and the [AlCl(4)](-) anions are predominantly ionic. The applicability of the Zintl concept to the chemical bonding in the heteronuclear polycation was evaluated by a thorough quantum chemical analysis.  相似文献   

15.
A series of new binuclear bis(catecholate) antimony(V) complexes based on 1,1′-spirobis[3,3-dimethylindanequinone-5,6] with various substituents at the central antimony atoms, R3Sb(Cat-Spiro-Cat)SbR3 (IIV) and R3Sb(CatBr-Spiro-BrCat)SbR3 (VVIII) (R = p-fluorophenyl, phenyl, p-tolyl, and ethyl), were synthesized. Spirobis(catecholates) IIII exhibit two one-electron oxidation waves on the cyclic voltammograms, whereas bromo-substituted spirobis(catecholates) VVII undergo two-electron oxidation immediately at the first stage. The two-electron oxidation of the complexes results in the loss of one of the organoantimony fragments and the formation of mononuclear catecholate-quinone complexes (Q-Spiro-Cat)SbR3 or (QBr-Spiro-BrCat)SbR3, respectively. An insignificant delocalization of the charge and spin between two redox centers is observed in the complexes. The nature of substituents at the antimony atom exerts an effect on the values of redox potentials of the complexes: more donating groups decrease the oxidation potentials of the catecholate fragments and more withdrawing groups increases these values.  相似文献   

16.
[Sb(12-Crown-4)2(CH3CN)][SbCl6]3 and [Bi(12-Crown-4)2(CH3CN)][SbCl6]3, first Trications of Antimony(III) and Bismuth(III) The crown ether complexes [M(12-crown-4)2(CH3CN)][SbCl6]3 with M = Sb and Bi are formed by the reaction of antimony trichloride and bismuth trichloride, respectively, with antimony pentachloride in acetonitrile solution in the presence of 12-crown-4. They form colourless, moisture sensitive crystals, which were characterized by X-ray structure determinations and by IR spectroscopy. The complex with M = Sb was also characterized by 121Sb Mössbauer spectroscopy. Both complexes crystallize isotypically in the orthorhombic space group Pbcn with four formula units per unit cell. M = Sb: 3 483 observed unique reflections, R = 0.038. M = Bi: 2 958 observed unique reflections, R = 0.036. The compounds consist of SbCl6? ions and trications [M(12-crown-4)2(CH3CN)]3+, in which the M3+ ions are ninefold coordinated by the eight oxygen atoms of the crown ether molecules and by the nitrogen atom of the acetonitrile molecule. The lone pair of the M3+ ions has no steric effect.  相似文献   

17.
In the present paper, we develop a methodology for antimony speciation in occupationally exposed human urine samples by high-performance liquid chromatography with hydride generation atomic fluorescence spectrometry (HPLC-HG-AFS). The methodology was applied to the determination of Sb(V), Sb(III) and (CH3)3SbCl2 (TMSb(V)). Retention time of Sb(V), Sb(III) and TMSb(V) species were 0.88, 2.00 and 3.61 and the detection limits were 0.18, 0.19 and 0.12 μg L− 1, for 100 μL loop injection respectively which is considered useful for elevated/occupationally exposed urine samples. Studies on the stability of antimony species in urine samples on the function of the elapsed time of preservation (4 °C) and storage (− 70 °C) were performed. Results revealed that antimony species are highly unstable at − 70 °C, probably due to co-precipitation reaction. In this kind of matrix transformation during preservation time may occur, such as oxidation of Sb(III) to Sb(V) and transformation into species that do not elute from the column. EDTA shows that it is able to stabilize Sb(III) for more than one week of preservation time at 4 °C avoiding co-precipitation during storage at − 70 °C. Finally the methodology was applied to occupationally exposed human urine samples. 25% of specimens present antimony levels (Sb(V)) of more than 5 μg L− 1.  相似文献   

18.
Tin dioxide and its antimony doped counterpart were synthesized using traditional sol–gel procedure. The metal oxides were then turned into composites by mixing them with polyacrylonitrile (PAN) and composite spheres ready for use in traditional column applications were obtained. The characterization of materials was investigated by X-ray diffraction, scanning electron microscopy–energy dispersive X-ray, surface area, point of zero charge and thermal analyses. Static batch experiments showed that the antimony doped tin dioxide–PAN (Sb doped SnO2–PAN) is an effective material for nickel removal and the composite maintains its good metal uptake properties in dynamic column conditions. The composite showed a high nickel uptake capacity of 9 mmol/g in 0.1 M NaNO3 solution. It was observed that the ion exchange kinetics of antimony doped tin dioxide (Sb doped SnO2) was remarkably fast for 57Co and 63Ni ions but turning the material into PAN composite significantly decreased the materials kinetic properties.  相似文献   

19.
The ternary polar intermetallic phase Mg(5.231(8))Sm(0.769(8))Sb4 has been obtained from solid-state reactions at 700-850 degrees C in sealed Ta or Nb containers when the synthetic conditions took into account its characteristic incongruent melting point. The compound crystallizes in the trigonal space group P3 (Z = 1) with a = 4.618(1) A and c = 14.902(6) A in a structure that derives from that of Mg3Sb2 (anti-La2O3 type). This composition appears to be near the lower limit of Sm content, and solutions with appreciably higher Sm contents are also stable [Mg(6-x)SmxSb4, x 相似文献   

20.
On the Limits of the Zintl Concept. The New Compound Ba7Ga4Sb9 The new compound Ba7Ga4Sb9 crystallizes in the orthorhombic system, space group Pmmn (No. 59) with the lattice constants GaSb4 tetrahedra are connected by common corners and edges to strings, which are connected by long Sb? Sb bonds to sheets, separated by the Ba ions. The compound is not in accordance to the Zintl concept.  相似文献   

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