Showing papers on "Antimony published in 2016"
TL;DR: Variable temperature 23Na NMR experiments reveal significant sodium mobility within c-Na3Sb; this is a possible contributing factor to the excellent rate performance of Sb anodes and is linked to the different reactivity of these networks.
Abstract: Operando pair distribution function (PDF) analysis and ex situ 23Na magic-angle spinning solid-state nuclear magnetic resonance (MAS ssNMR) spectroscopy are used to gain insight into the alloying mechanism of high-capacity antimony anodes for sodium-ion batteries. Subtraction of the PDF of crystalline NaxSb phases from the total PDF, an approach constrained by chemical phase information gained from 23Na ssNMR in reference to relevant model compounds, identifies two previously uncharacterized intermediate species formed electrochemically; a-Na3–xSb (x ≈ 0.4–0.5), a structure locally similar to crystalline Na3Sb (c-Na3Sb) but with significant numbers of sodium vacancies and a limited correlation length, and a-Na1.7Sb, a highly amorphous structure featuring some Sb–Sb bonding. The first sodiation breaks down the crystalline antimony to form first a-Na3–xSb and, finally, crystalline Na3Sb. Desodiation results in the formation of an electrode formed of a composite of crystalline and amorphous antimony networks...
171 citations
TL;DR: Comparison of the biogeochemistry of As and Sb in water/fish, soil/vegetable, tailings/plant samples were carried out at the world's largest active Sb mine area (Xikuangshan, China), and significant differences in spatial distributions were found.
151 citations
TL;DR: The current understanding of antimony biochemistry and biogeochemistry is roughly equivalent to where that of arsenic was some 20 years ago, indicating the possibility of future discoveries with regard to the ability of microorganisms to conserve energy for their growth from antimony redox reactions and the isolation of new species of “antimonotrophs.”
Abstract: Antimony (Sb) is a toxic metalloid that occurs widely at trace concentrations in soil, aquatic systems, and the atmosphere. Nowadays, with the development of its new industrial applications and the corresponding expansion of antimony mining activities, the phenomenon of antimony pollution has become an increasingly serious concern. In recent years, research interest in Sb has been growing and reflects a fundamental scientific concern regarding Sb in the environment. In this review, we summarize the recent research on bacterial antimony transformations, especially those regarding antimony uptake, efflux, antimonite oxidation, and antimonate reduction. We conclude that our current understanding of antimony biochemistry and biogeochemistry is roughly equivalent to where that of arsenic was some 20 years ago. This portends the possibility of future discoveries with regard to the ability of microorganisms to conserve energy for their growth from antimony redox reactions and the isolation of new species of "antimonotrophs."
127 citations
TL;DR: In this paper, the authors showed that using potassium ferrate is a viable water treatment technology to remediate arsenic and antimony combined pollution, and demonstrated that using a single-solute and a bi-solastic system is more efficient.
106 citations
TL;DR: In this article, a review summarizes the available literature on antimony in the environment and its removal with emphasis on effluent treatment with respect to industrial effluents and their treatment is presented, where antimony speciation as well as oxidation was presented at various conditions (pH, E h, temperature, and concentration).
103 citations
TL;DR: Antimony has become an increasingly critical element in recent years, due to a surge in industrial demand and the Chinese domination of primary production as mentioned in this paper, which has sparked efforts to find secondary sources of antimony either through the recycling of end-of-life products or by recovering antimony from industrial process residues.
Abstract: Antimony has become an increasingly critical element in recent years, due to a surge in industrial demand and the Chinese domination of primary production. Antimony is produced from stibnite ore (Sb2O3) which is processed into antimony metal and antimony oxide (Sb2O3). The industrial importance of antimony is mainly derived from its use as flame retardant in plastics, coatings, and electronics, but also as decolourizing agent in glass, alloys in lead-acid batteries, and catalysts for the production of PET polymers. In 2014, the European Commission highlighted antimony in its critical raw materials report, as the element with the largest expected supply–demand gap over the period 2015–2020. This has sparked efforts to find secondary sources of antimony either through the recycling of end-of-life products or by recovering antimony from industrial process residues. Valuable residues are obtained by processing of gold, copper, and lead ores with high contents of antimony. Most of these residues are currently discarded or stockpiled, causing environmental concerns. There is a clear need to move to a more circular economy, where waste is considered as a resource and zero-waste valorization schemes become the norm, especially for rare elements such as antimony. This paper gives a critical overview of the existing attempts to recover antimony from secondary sources. The paper also discusses the possibility of waste valorization schemes to guarantee a more sustainable life cycle for antimony.
103 citations
92 citations
TL;DR: Antimony film electrodes (SbFEs) as mentioned in this paper offer some interesting characteristics such as favorably negative overvoltage of hydrogen evolution, wide operational potential window, convenient operation in acidic solutions of pH 2 or lower and a small Sb stripping signal.
Abstract: This review summarizes analytical determinations carried out using antimony film electrodes (SbFEs), an environmentally safe option that constitutes an alternative not only to the most conventional Hg-based electrodes but also to Bi-based electrodes. SbFEs offer some interesting characteristics such as favorably negative overvoltage of hydrogen evolution, wide operational potential window, convenient operation in acidic solutions of pH 2 or lower and a very small Sb stripping signal. The substrate on which the Sb was plated is used to classify the types of SbFEs. Moreover, we detail the method of coating the substrate with Sb as well as the Sb modifiers. We present tables with the most important information from the accessible literature.
86 citations
TL;DR: In this article, Antimony sulfide films have been deposited by pulse electrodeposition on Fluorine doped SnO2 coated glass substrates from aqueous solutions containing SbCl3 and Na2S2O3, and the crystalline structure of the films was characterized by X-ray diffraction, Raman spectroscopy and TEM analysis.
74 citations
TL;DR: Among antimony(III) compounds with sulfur containing ligand, those of dithiocarbamates exhibit significant cytotoxic activity, which makes this compound candidate for further study as potential drug.
66 citations
TL;DR: The obtained detection and quantification limits suggest that the in-situ antimony film electrode prepared from carbon nanofibers modified screen-printed electrode (SbSPCE-CNF) produces a better analytical performance as compared to the classical SPCE modified with antimony for Pb( II) and Cd(II) determination.
TL;DR: In this paper, the effects of SbI3 addition to CH3NH3Pb1−SbxI3 precursor solutions on photovoltaic properties were investigated.
Abstract: Effects of SbI3 addition to CH3NH3PbI3 precursor solutions on the photovoltaic properties were investigated. TiO2/CH3NH3Pb1−xSbxI3-based photovoltaic devices were fabricated in air, and formation o...
TL;DR: In this paper, the pH-dependent leaching of antimony and arsenic from three typical Sb-bearing ores (Banxi, Muli and Tongkeng Antimony Mine) in China was assessed using a pH-static leaching experiment.
Abstract: The pH-dependent leaching of antimony (Sb) and arsenic (As) from three typical Sb-bearing ores (Banxi, Muli and Tongkeng Antimony Mine) in China was assessed using a pH-static leaching experiment. The pH changes of the leached solutions and pH-dependent leaching of Sb and As occurred in different ways. For the Banxi and Muli Sb ores, alkaline conditions were more favorable for the release of Sb compared to neutral and acidic conditions, but the reverse was true for the pH-dependent release of As. For the Tongkeng Sb ore, unlike the previous two Sb-bearing ores, acidic conditions were more favorable for Sb release than neutral and alkaline conditions. The ores with lower Sb and As contents released higher percentages of their Sb and As after 16day leaching, suggesting that they are the largest potential sources of pollution. This work may provide key information on the geochemistry of Sb and As in the weathering zone.
TL;DR: In this article, Sb-polluted water was treated by application of a mixed batch culture of sulfate-reducing bacteria (SRB) over an initial pH range 5-8.
TL;DR: In this paper, a hybrid carbon encapsulation strategy was proposed to improve the anode performance of antimony through the combination of Sb/N-carbon hybrid nanostructures and the carbon nanotube (CNT) network.
Abstract: Antimony is a promising high-capacity anode material in sodium-ion batteries, but it generally shows poor cycling stability because of its large volume changes during sodium ion insertion and extraction processes. To alleviate or even overcome this problem, we develop a hybrid carbon encapsulation strategy to improve the anode performance of antimony through the combination of antimony/nitrogen-doped carbon (Sb/N-carbon) hybrid nanostructures and the carbon nanotube (CNT) network. When evaluated as an anode material for sodium-ion batteries, the as-synthesized Sb/N-carbon + CNT composite exhibits superior cycling stability and rate performance in comparison with Sb/N-carbon or Sb/CNT composite. A high charge capacity of 543 mA h g–1 with initial charge capacity retention of 87.7% is achieved after 200 cycles at a current density of 0.1 A g–1. Even under 10 A g–1, a reversible capacity of 258 mA h g–1 can be retained. The excellent sodium storage properties can be attributed to the formation of Sb–N bondin...
TL;DR: In this article, the authors investigated whether such an ambitious extraction reduction goal would be technically feasible, without losing any of the current services that are provided by antimony, and they concluded that about 95% of antimony in flame retardants can be replaced by other components or systems.
Abstract: Antimony is an element that is applied in many useful applications for mankind. However, antimony resources are very scarce, when comparing the current extraction rates with the availability of antimony containing ores. From an inter-temporal sustainability perspective, current generations should not deprive future generations from extractable ores. The extraction rate of a mineral resource is defined sustainable, if such a rate can be sustained for 1000 years assuming the same consumption per capita in all countries of the world. To achieve a sustainable extraction of antimony, it is necessary to reduce the current extraction with 96% compared to the primary antimony extraction in 2010. We have investigated whether such an ambitious extraction reduction goal would be technically feasible, without losing any of the current services that are provided by antimony. Reduction of the use of primary antimony can be achieved through (a combination of) substitution, improved material efficiency and recycling. Because the potential of material efficiency and recycling are limited in the case of antimony, the focus is on substitution of antimony in its applications. The major application of antimony (more than 50%) is in flame retardants. It appears that about 95% of antimony in flame retardants can be replaced by other components or systems. Overall, the substitutability of antimony in all its applications is estimated at around 90%. The required additional extraction reduction needs to be realized by improved material efficiency and further recycling, especially from the remaining antimony containing flame retardants and from lead-alloys.
TL;DR: In this paper, a new alkaline oxidative pressure leaching process was developed to remove arsenic from antimony bearing dusts, and the effect of NaOH concentration, oxygen partial pressure, temperature, liquid/solid ratio and reaction time on the leaching of arsenic, antimony and lead were investigated.
TL;DR: By introduction of a distinct secondary electrolyte, this work reveals a high-throughput electro-desulfurization process that directly converts semiconducting molten stibnite into pure (99.9%) liquid antimony and sulfur vapour.
Abstract: Metals cannot be extracted by electrolysis of transition-metal sulfides because as liquids they are semiconductors, which exhibit high levels of electronic conduction and metal dissolution. Herein by introduction of a distinct secondary electrolyte, we reveal a high-throughput electro-desulfurization process that directly converts semiconducting molten stibnite (Sb2S3) into pure (99.9%) liquid antimony and sulfur vapour. At the bottom of the cell liquid antimony pools beneath cathodically polarized molten stibnite. At the top of the cell sulfur issues from a carbon anode immersed in an immiscible secondary molten salt electrolyte disposed above molten stibnite, thereby blocking electronic shorting across the cell. As opposed to conventional extraction practices, direct sulfide electrolysis completely avoids generation of problematic fugitive emissions (CO2, CO and SO2), significantly reduces energy consumption, increases productivity in a single-step process (lower capital and operating costs) and is broadly applicable to a host of electronically conductive transition-metal chalcogenides.
TL;DR: In this article, spray pyrolised CuSbS2 thin films were synthesized and characterized using X-ray diffraction, Raman spectroscopy, Xray photoelectron spectrography, atomic force microscopy, UV-visible spectrograms, and Hall effect measurements.
Abstract: Copper antimony sulfide (CuSbS2) thin films have been gained interest recently as an emerging light absorbing material for photovoltaic applications. In this work we report synthesis and characterization of spray pyrolised CuSbS2 thin films. The precursor solution consisted of SbCl3, CuCl2 and NH2CSNH2 dissolved ethanol. The substrate temperature was kept at 200 °C. Samples were prepared at different molar ratios of Cu:Sb:S. These thin films were characterized using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, UV-visible spectroscopy, photocurrent and Hall effect measurements. P-type CuSbS2 thin films of orthorhombic structure were formed and the films showed photocurrent response. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
TL;DR: This study has demonstrated that the stable isotopes of (34)SSO4 and (87)Sr, combined with hydrochemical methods, are effective in tracking the sources, migration and transformation of Sb contamination.
TL;DR: In this paper, an antimony-doped CeO2-WO3/TiO2 was used for selective catalytic reduction of NOx with NH3 at low temperature.
Abstract: Antimony-doped CeO2–WO3/TiO2 catalysts were prepared by a conventional ultrasonic-assisted impregnation method and employed for selective catalytic reduction of NOx with NH3 at low temperature. Both experimental work and theoretical studies were employed to elucidate the effect of the antimony on promoting the CeO2–WO3/TiO2 catalyst. The catalytic activity of CeO2–WO3/TiO2 was largely improved after the addition of antimony oxide. It was found that antimony doping reduced the crystal size and strengthened the synergistic effect between the metal cations, which resulted in a favorable catalyst surface status with abundant active surface oxygen, Bronsted acid sites, and effective electron transfer. Both in situ diffuse reflectance infrared Fourier transform analysis and DFT calculation results revealed that the ammonia and NOx desorption behavior over the catalyst surface were considerably different. For the ammonia species, rather large amounts of the active NH4+ and NH3 species anchored on the surface of the Sb-doped CeO2–WO3/TiO2. In view of the NOx species, the amount of nonactive bidentate nitrate species was largely reduced and the amount of active gaseous NO2 species was clearly enhanced, which lowered the activation energy of the catalytic process and gave rise to the elevated low-temperature NH3 selective catalytic reduction activity. All these preferable properties resulted in the elevated de-NOx activity of the Sb-doped CeO2–WO3/TiO2 catalyst.
TL;DR: In this paper, a combination of mineralogical and geochemical studies was used to characterize two occurrences with an abundance of the supergene Sb minerals brandholzite and peretaite.
Abstract: Environmental context Antimony enters the environment from tailings and mines but there are widely divergent statements about its mobility in the environment. This work addresses the question of mobility of Sb by a combination of mineralogical and geochemical studies. Abstract This work characterises two occurrences with an abundance of the supergene Sb minerals brandholzite [Mg[Sb(OH)6]2·6H2O], klebelsbergite [Sb4O4(OH)2(SO4)] and peretaite [CaSb4O4(OH)2(SO4)2·2H2O]. Brandholzite forms from near-neutral waters, where stibnite (Sb2S3) decomposes in the presence of abundant carbonates. The SbIII sulfates form from acidic waters, where stibnite decomposes in the presence of marcasite or pyrite (FeS2). These initial supergene minerals form rapidly (brandholzite within weeks) and supply Sb into local waters. Calculation of saturation indices from underground water (present study) and many waters discharged from Sb mines (data from the literature) show that brandholzite (and related soluble Sb minerals) are undersaturated. Hence, if they do exist, they should dissolve. Insoluble Sb phases, such as tripuhyite (FeSbO4) are grossly supersaturated, but do not form (or form very slowly). Hence, we conclude that the mobility of antimony observed in geochemical studies is due to the solubility of the initial supergene minerals. The immobility of antimony stated in mineralogical studies is due to the slow but persistent formation of insoluble tripuhyite. When the kinetics of formation of these minerals are taken into account, the widely divergent statements about mobility or immobility of antimony in the environment can be reconciled.
TL;DR: Ferric oxides and hydroxides are assumed to be principal mineral phases for arsenic and antimony attenuation by adsorption/co-precipitation processes to determine their distribution model in water-sediment system and its compatibility with the existing theoretical model.
TL;DR: In this paper, the authors compared the removal capability and mechanisms involved in the removal of aqueous Sb by non-doped and Cu-depleted Fe3O4 (magnetite).
Abstract: This study compared the removal capability and mechanisms involved in the removal of aqueous Sb by non-doped and Cu-doped Fe3O4 (magnetite). After doping Cu into Fe3O4, it exhibited a smaller particle size with slightly declined saturation magnetization, and enhanced antimony adsorptive capability. Non-doped Fe3O4 showed a maximum adsorption capacity (Qmax) of 34.46 mg Sb(III) g−1 and 7.07 mg Sb(V) g−1 at pH 7.0. The doping of Cu improved the Sb adsorption with a Qmax of 43.55 mg Sb(III) g−1 and 30.92 mg Sb(V) g−1 accordingly. The co-existing sulfate and carbonate had a negligible effect on Sb removal; however, phosphate at 10 mM decreased the Sb(III) and Sb(V) removal by 50.1% and 18.2% for Fe3O4 and by 14.1% and 58.6% for Cu-doped Fe3O4. As for Cu-doped Fe3O4, the results indicated that the Sb(III) oxidation on CuII–O sites was much more significant than that on FeIII–O sites and the dissolution oxygen amount did not affect this process. Upon the electron transfer from Sb(III) to Cu(II), the formed Cu(I) and Sb(V) tends to release into the solution and the Cu(I) disproportionates to give Cu(II) ions and a precipitate of Cu(0) thereafter. The magnetic Cu-doped Fe3O4 shows good removal efficiency towards both Sb(III) and Sb(V) and is a potential adsorbent for Sb removal in practice.
TL;DR: In this article, the authors synthesize antimony sulphide thin films on glass substrate by physical vapour deposition technique, and the obtained films were then annealed at different temperatures (150-250 °C).
Abstract: Replacement of the toxic, expensive and scarce materials with nontoxic, cheap and earth-abundant one, in solar cell absorber layer, is immensely needed to realize the vision of green and sustainable energy. Two-micrometre-thin antimony sulphide film is considered to be adequate as an absorbing layer in solar cell applications. In this paper, we synthesize antimony sulphide thin films on glass substrate by physical vapour deposition technique, and the obtained films were then annealed at different temperatures (150–250 °C). The as-deposited and annealed samples were investigated for structural and optoelectronic properties using different characterization techniques. The X-ray diffraction analysis showed that the annealed samples were polycrystalline with Sb2S3 phase, while the as-deposited sample was amorphous in nature. The optical properties are measured via optical ellipsometric techniques. The measured absorbance of the film is adequately high, and every photon is found to be absorbed in visible and NIR range. The conductivity type of the films measured by hot-point probe technique is determined to be p-type. The optical band gap of the resulted samples was in the range (2.4–1.3 eV) for the as-deposited and annealed films.
TL;DR: In this article, the results showed that the leaching efficiency of antimony increases with the temperature (from 35°C to 65°C) and hydrochloric acid concentration (from 3.0 to 4.5 mol/L).
TL;DR: The goal of this work was to develop an analytical procedure exploiting for the first time the cloud point extraction on a lab-in-syringe flow system aiming at the spectrophotometric determination of antimony, yielding results in agreement with those obtained by HGFAAS at the 95% confidence level.
TL;DR: In this paper, the perovskite properties including oxygen nonstoichiometry (δ), mean valence of B-site, tolerance factors, thermal expansion coefficient (TEC) and electrical conductivity (σ) are explored as a function of antimony content.
TL;DR: This paper proposed a multisyringe flow injection analysis (MSFIA) system for antimony, arsenic and selenium determination in peanut samples by hydride generation atomic fluorescence spectrometry (HG-AFS) using the certified peach leaves reference material SRM 1547.
TL;DR: In this paper, the effect of GeO 2 /Sb 2 O 3 ratio in fabricated glass doped with samarium ions on thermal, structural and luminescent properties was investigated.