首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 273 毫秒
1.
New complexes catena‐(μ2‐nitrato‐O,O′)bis(piperidinedithiocarbamato)bismuth(III) ( 1 ) and tetrakis(μ‐nitrato)tetrakis[bis(tetrahydroquinolinedithiocarbamato)bismuth(III)] ( 2 ) were synthesised and characterised by elemental analysis, FTIR spectroscopy and thermogravimetric analysis. The single‐crystal X‐ray structures of 1 and 2 were determined. The coordination numbers of the BiIII ion are 8 for 1 and ≥6 for 2 when the experimental electron density for the nominal 6s2 lone pair of electrons is included. Both complexes were used as single‐source precursors for the synthesis of dodecylamine‐, hexadecylamine‐, oleylamine and tri‐n‐octylphosphine oxide‐capped Bi2S3 nanoparticles at different temperatures. UV/Vis spectra showed a blueshift in the absorbance band edge characteristic of a quantum size effect. High‐quality, crystalline, long and short Bi2S3 nanorods were obtained depending on the thermolysis temperature, which was varied from 190 to 270 °C. A general trend of increasing particle breadth with increasing reaction temperature and increasing length of the carbon chain of the amine (capping agent) was observed. Powder XRD patterns revealed the orthorhombic crystal structure of Bi2S3.  相似文献   

2.
This article deals with complex formation of Bi(III) with 3-mercaptopropanesulfonic acid (H2MPS) in aqueous perchloric acid solutions, with synthesis and characterization of a solid 3-mercaptopropanesulfonate complex of bismuth(III). The stoichiometry and structures of Bi-MPS species in aqueous solution and of a solid complex have been studied by UV–Vis, 1H-NMR, ICP-AES, Raman, and EXAFS spectroscopic methods; the structures have also been simulated with DFT/PBE0 calculations. The Bi(III) LIII-edge EXAFS oscillation for a solid compound with the empirical formula [Bi(HMPS)2(ClO4)]0 was simulated with two Bi–S interatomic distances at 2.50 ± 0.01 Å, two Bi–O distances at 2.56 ± 0.02 Å and two Bi–O distances at 2.75 ± 0.02 Å. Implementation of the same approach for aqueous solutions on the assumption of S3BiO3 coordination at the H2MPS?:?Bi(III) mole ratio ≥ 3.0 revealed three Bi–S bonds at 2.53 ± 0.02 Å and three Bi–O bonds at 2.68 ± 0.02 Å, respectively. Optimized geometries, electronic structures of Bi(HMPS)3 and [Bi(HMPS)2ClO4]0, vibrational properties of [Bi(HMPS)2ClO4]0, and electronic absorption spectrum of Bi(HMPS)3 species obtained by DFT and TD–DFT modeling are consistent with empirical parameters. In the UV–Vis spectrum of Bi(HMPS)3 the LMCT and MLCT S2? ? Bi3+ band appears at 268 nm.  相似文献   

3.
Powder X-ray diffraction, IR spectroscopy, Raman spectroscopy, thermogravimetry, and chemical analysis were used to study the precipitation of bismuth(III) salicylates from perchloric, nitric, and hydrochloric acid solutions as dependent on the salicylate ion concentration, temperature, and pH. Depending on the synthesis parameters, precipitation from perchloric and nitric acid solutions yields monosalicylate BiOC7H5O3 or disalicylate Bi2O(C7H5O3)4.  相似文献   

4.
Bismuth sulfide (Bi2S3) nanomaterials are emerging as a promising theranostic platform for computed tomography imaging and photothermal therapy of cancer. Herein, the photothermal properties of Bi2S3 nanorods (NRs) were unveiled to intensely correlate to their intrinsic deep‐level defects (DLDs) that potentially could work as electron–hole nonradiative recombination centers to promote phonon production, ultimately leading to photothermal performance. Bi2S3‐Au heterojunction NRs were designed to hold more significant DLD properties, exhibiting more potent photothermal performance than Bi2S3 NRs. Under 808 nm laser irradiation, Bi2S3‐Au NRs could trigger higher cellular heat shock protein 70 expression and more apoptotic cells than Bi2S3 NRs, and caused severe cell death and tumor growth inhibition, showing great potential for photothermal therapy of cancer guided by computed tomography imaging.  相似文献   

5.
For the first time, carbon screen‐printed electrodes (CSPE) modified with bismuth nanoparticles have been used to determine sulfide ions with stripping voltammetry (SV) by formation of sparingly soluble compounds with the electrode material. The impact of weight, degree of bismuth dispersion on CSPE surface, and Bi2S3 accumulation parameters on the sensitivity of the sensor have been studied. It has been established that bismuth nanoparticles (Binano) as agglomerates of about 180 nm exhibit the optimum sensory properties. The linear concentration range has been observed over the interval of 0.93–5 µM sulfide ions during the accumulation time of 75 s. A detection limit of 0.15 µM sulfide ions was achieved.  相似文献   

6.
《Polyhedron》1999,18(21):2775-2780
Triclinic crystals of bismuth(III) triple-decker phthalocyanine, Bi2Pc3, Pc=C32H16N82−, were grown directly by the reaction of Bi2Se3 with 1,2-dicyanobenzene at 220°C. The Bi2Pc3 molecule is centrosymmetric with the bismuth atoms located closer to the peripheral phthalocyaninato(2−) rings than to the central ring. Each bismuth(III) ion is connected by four N-isoindole atoms to the peripheral and by four N-isoindole to the central Pc ring with average distances of 2.333 and 2.747 Å, respectively. This indicates a stronger connection of Bi(III) to the peripheral saucer-shaped macrocyclic rings than to the central rings. The neighbouring phthalocyaninato(2−) moieties in the Bi2Pc3 molecule are separated by a distance of 3.101(5) Å. The central Pc ring is rotated by 36.4° with respect to the peripheral ones. Differences in Bi–N bond lengths are a result of interaction of the bismuth ion with peripheral and central rings as well as the repulsion forces between two bismuth ions in the same Bi2Pc3 molecule, which are separated by a distance of 3.839(2) Å. The crystal packing is characterized by a distance of 3.56 Å between Pc rings of neighbouring Bi2Pc3 molecules.  相似文献   

7.
{[Bi(BTC)(H2O)2] · H2O}n (H3BTC = 1,3,5‐benzenetricarboxylic acid) was synthesized by an eco‐friendly hydrothermal method and characterized by single‐crystal X‐ray diffraction, IR and UV/Vis spectroscopy, photoluminescence (PL), and thermogravimetric analyses. The complex featured a 3D metal‐organic framework with Bi2 secondary building units. In the complex, the central Bi3+ is nine‐coordinate, three central Bi atoms and three BTC3– anions are interconnected into a ring with the dimension of 7.95 × 9.89 Å2. Moreover, the complex is decomposed at over 388 °C, showing its highly thermal stability. Further, the complex exhibits photocatalytic activity for the degradation of methyl orange (MO) solution under UV light irradiation, and its structure can keep consistent with the original one after 9 h photocatalytic reaction, indicating that it is also very stable under UV light. Therefore, it could be anticipated the novel coordination complex will be a stable ultraviolet light catalyst.  相似文献   

8.
Bismuth titanate (Bi4Ti3O12) was developed by means of titanium oxide (TiO2) suspension in auto-combustion process at 220 °C to get nanosized (20 ± 5 nm) bismuth titanate (Bi4Ti3O12) powder. Complete piezoelectric phase (tetragonal) was obtained after calcination at 700 °C. Dilatometery of compacts was performed to find out sintering temperature. On the basis of shrinkage results, compacts were sintered at 750, 800, and 850 °C for 2 h. After sintering single phase was obtained with orthorhombic structure analyzed by X-ray diffraction and also investigated by Rietveld method. High-resolution scanning electron microscopy revealed that fine plate-like structure which is a characteristic of BIT powder can be obtained at 850 °C. Sintering results indicate that density and average grain size increase with the increasing temperature. A maximum of about 90 % of the theoretical density was achieved for the sintered product at 850 °C.  相似文献   

9.
An Anionic Oxohydroxo Complex with Bismuth(III): Na6[Bi2O2(OH)6](OH)2 · 4H2O Colourless, plate‐like, air sensitive crystals of Na6[Bi2O2(OH)6](OH)2 · 4H2O are obtained by reaction of Bi2O3 or Bi(NO3)3 · 5H2O in conc. NaOH (58 wt %) at 200 °C followed by slow cooling to room temperature. The crystal structure (triclinic, P 1¯, a = 684.0(2), b = 759.8(2), c = 822.7(2) pm, α = 92.45(3)°, ß = 90.40(3)°, γ = 115.60(2)°, Z = 1, R1, wR2 (all data), 0, 042, 0, 076) contains dimeric, anionic complexes [Bi2O2(OH)6]4— with bismuth in an ψ1‐octahedral coordination of two oxo‐ and three hydroxo‐ligands. The thermal decomposition was investigated by DSC/TG or DTA/TG and high temperature X‐ray powder diffraction measurements. In the final of three steps the decomposition product is Na3BiO3.  相似文献   

10.

The quest for developing the scalable methods of synthesis of materials with potential electrochemical energy storage applications remains a great challenge. Herein, we propose a facile, one-step chemical precipitation method for the synthesis of Bi2S3 with the nanorods morphology. Influence of different synthesis temperatures on the physical, chemical, and electrochemical performance was investigated. Relatively low BET surface area and mesopore volume of Bi2S3 increased with the higher reaction temperature. Bismuth sulfides synthesized at various temperatures were used as an electrode active material in supercapacitor. The semiconductive properties of Bi2S3 resulted in exceptional capacitive behavior. Bismuth sulfide synthesized at 75 °C exhibited a specific capacitance of 457 F g−1 at 1 A g−1 in 6 mol L−1 KOH solution as an electrolyte. Moreover, material prepared at 75 °C maintained the best capacitance value at a large current density of 20 A g−1, compared with bismuth sulfides synthesized at the temperatures of 0 °C and 25 °C.

  相似文献   

11.
In this paper, Bi2O3 and rare earth (La, Ce)‐doped Bi2O3 visible‐light‐driven photocatalysts were prepared in a Triton X‐100/n‐hexanol/cyclohexane/water reverse microemulsion. The resulting materials were characterized by X‐ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) surface area, photoluminescence spectra (PLS) and UV–Vis diffuse reflectance spectroscopy. The XRD patterns of the as‐prepared catalysts calcined at 500°C exhibited only the characteristic peaks of monoclinic α‐Bi2O3. PLS analysis implied that the separation efficiency for electron‐hole has been enhanced when Bi2O3 was doped with rare earth. UV–Vis diffuse reflectance spectroscopy measurements presented an extension of light absorption into the visible region. The photocatalytic activity of the samples was evaluated by degradation of methyl orange (MO) and 2,4‐dichlorophenol (2,4‐DCP). The results displayed that the photocatalytic activity of rare earth‐doped Bi2O3 was higher than that of dopant‐free Bi2O3. The optimal dopant amount of La or Ce was 1.0 mol%. And the mechanisms of influence on the photocatalytic activity of the catalysts were discussed.  相似文献   

12.
The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal microbalance, X-ray diffraction, and energy dispersive X-ray analysis methods. During the bismuth sulfide coating reduction in Watts background electrolyte in the potential region from −0.4 to −0.6 V, the Bi2S3 and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S2− ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed increase in coating mass in the potential region −0.1 to −0.4 V is conditioned by Ni2+ ions reduction before the bulk deposition of Ni, initiated by Bi2S3. In this potential region, the reduction of Bi(III) oxygen compounds can occur. After the treatment of as-deposited bismuth sulfide coating in nickel plating electrolyte at E = −0.3 V, the sheet resistance of the layer decreases from 1013 to 500–700 Ω cm. A metal-rich mixed sulfide Ni3Bi2S2–parkerite is obtained when as-deposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential close to the equilibrium potential of the Ni/Ni2+ system and then annealed at temperatures higher than 120 °C.  相似文献   

13.
Bismuth sulfide (Bi2S3) is a promising anode material for high-performance potassium ion batteries due to its high theoretical capacity.However,the poor conductivity and substantial volume expansion hinder its practical application.We proposed an iodine-doped graphene encapsulated Bi2S3nanorods composite(Bi2S3/IG) as an efficient anode for PIBs.The uniform-sized Bi2S3nanorods evenly in-situ encapsulated in io...  相似文献   

14.
Uniform Bi2WO6 pancakes were prepared via a solvothermal route in a solvent mixture of glycerol (Gly) and water (V/V = 1). A variety of techniques including scanning electron microscopy, transmission electron micrographs, X-ray powder diffraction, Brunauer–Emmett–Teller, FT-IR spectra, and UV–Vis diffuse reflectance spectra, were employed to characterize the structure and properties of the as-obtained Bi2WO6. It was found that Bi2WO6 pancakes showed prominent photocatalytic performance for the degradation of rhodamine B (RhB) under visible light (λ ≥ 420 nm) irradiation, which can be attributed to its good crystallization, large surface area, unique morphology and structural features.  相似文献   

15.
Bismuth oxide cluster ions are reduced by propene in exactly the same way as solid bismuth oxide (Bi2O3), which is used as a catalyst. Even in the case of the smallest bismuth oxide cluster ions, such as the Bi3O4+ isomer shown in the picture, the supposedly unreactive bridging oxygen atom can participate in the alkene oxidation.  相似文献   

16.
β- and α-phase porous Bi2O3 microspheres with an average size of around 4 μm had been synthesized by thermal treatment of Bi2O2CO3 microspheres at 350 and 400–500 °C respectively in an air atmosphere. The Bi2O2CO3 microspheres had been synthesized at a temperature of 180 °C by a hydrothermal process using Bi(NO3)3 as the bismuth source with the assist of citric acid. By combining the results of X-ray powder diffraction, transmission electron microscope, scanning electron microscopy, and UV–Visible absorption spectra, the structural, morphological and optical properties characterization of the products were performed. The photocatalytic activity of the as-prepared α- and β-phase porous Bi2O3 microspheres have been tested by degradation of methylene orange under visible light, indicating that porous β-Bi2O3 microspheres showed enhanced photocatalytic performance compared to P25 and α-Bi2O3 microspheres.  相似文献   

17.
BiIII‐MOFs 1 – 4 were prepared via solvothermal method using four organic linkers; 2‐mercapto‐3‐methyl‐4‐thiazoleacetic acid (H2MMTA), 2,6‐naphthalenedicarboxylic acid (2,6‐NDA), 4,6‐dihydroxy‐2‐mercaptopyrimidine (H2DMP), and 4‐mercaptobenzoic acid (H2MBA), respectively. The resulting MOFs were structurally/morphologically characterized by UV/Vis, AAS/ICP‐MS, Fourier transform infrared spectroscopy (FT‐IR), 1H NMR, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and powder X‐ray diffraction technique. All these MOFs showed good luminescence properties exhibiting blue luminescence. N2 gas adsorption isotherms of 1 – 4 confirmed the porosity of these frameworks. In order to evaluate the effect of metal ion upon chelation, the free organic linkers and respective MOFs were screened for their antibacterial potential against some pathogenic bacteria and appreciable activity was observed.  相似文献   

18.
The crystal and molecular structures of bismuth(III) dimethyldithioarsinate, Bi(S2AsMe2)2, were investigated by X-ray diffraction. The compound is a centrosymmetric dimer in which pentagonal-bipyramidal monomeric units are associated through secondary Bi–S interactions. The structure is compared with that of the analogous dithiophosphinate, Bi(S2PMe2)2. © 1997 John Wiley & Sons, Inc.  相似文献   

19.
More than 80 years after Paneth’s report of dimethyl bismuth, the first monomeric BiII radical that is stable in the solid state has been isolated and characterized. Reduction of the diamidobismuth(III) chloride Bi(NONAr)Cl (NONAr=[O(SiMe2NAr)2]2−; Ar=2,6‐iPr2C6H3) with magnesium affords the BiII radical .Bi(NONAr). X‐ray crystallographic measurements are consistent with a two‐coordinate bismuth in the +2 oxidation state with no short intermolecular contacts, and solid‐state SQUID magnetic measurements indicate a paramagnetic compound with a single unpaired electron. EPR and density functional calculations show a metal‐centered radical with >90 % spin density in a p‐type orbital on bismuth.  相似文献   

20.
A hexadentate dibasic thioether N2O2S2 donor ligand (H 2 L) and its octahedral nickel(II) complex, [Ni(L)] have been synthesized and characterized by physicochemical and spectroscopic techniques. The structures of both H 2 L and its nickel complex were confirmed by single-crystal X-ray diffraction studies. The cyclic voltammogram of the complex shows a quasi-reversible Ni(II)/Ni(III) oxidation couple (E 1/2 = 0.88 V) along with a ligand-based reduction (E 1/2 = ?0.83 V). The electronic structures and electrochemical properties have been interpreted with the help of DFT calculations. The electronic transitions as calculated by TDDFT/CPCM method are used to assign the UV–Vis absorption bands.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号