Role Of Antimony Research Articles

The role of antimony in tailoring optical properties of spray pyrolysis synthesized pbse/sb thin films for solar device optimization

The role of antimony in tailoring optical properties of spray pyrolysis synthesized pbse/sb thin films for solar device optimization

Investigation on the Role of antimony in CdTe QDs sensitized solar cells

In this work, the effect of Sb doping on the structural, optical and photovoltaic properties of the CdTe quantum dots (QDs) were reported. Sb doped CdTe (SDC) QDs were synthesized with different dopant concentration in aqueous phase. Prepared QDs were analytically characterized for their structural, optical and compositional informations. Prepared SDC QDs possessed cubic zinc blende crystalline structure, which was revealed through XRD studies. XRD patterns also elucidate that the crystalline nature was not altered by the dopant ion incorporation. The optical response of SDC QDs revealed the size and dopant dependent optical properties. Presence of different functional groups and it's composition confirmed the formation of SDC QDs and it also confirmed the superior capping effect of thiol capping agent. Formation of SDC QDs was further confirmed by XPS analysis through binding energy variation of individual elements. Sandwich type QDs senstized solar cell was fabricated to study the photovoltaic response of the prepared QDs. At the standard illumination condition, Sb doped CdTe QDs sensitized TiO2 photoanodes showed superior photovoltaic response than pure CdTe QDs.

Microwave-Assisted Synthesis of Nitrogen and Sulphur Doped Graphene Decorated with Antimony Oxide: An Effective Catalyst for Oxygen Reduction Reaction.

In this study, we report on the facile synthesis of a novel electrocatalysts for the oxygen reduction reaction (ORR), based on reduced graphene oxide (RGO), functionalized with metallic and non-metallic elements. In particular, thanks to a fast one-pot microwave-assisted procedure, we induced, in the RGO graphene lattice, a combined doping with nitrogen and sulphur, and the simultaneous decoration with antimony oxide nanocrystals. The multi-doped–decorated material shows enhanced catalytic performance towards ORR, with respect to common nitrogen- or sulphur-doped carbon-based materials. The presence of co-doping is confirmed by transmission electron microscopy and X-ray photoelectron spectroscopy analysis. The detailed electrochemical characterization shows the simultaneous effects of dopant atoms on the catalytic behavior. In particular, the importance of nitrogen and sulphur atoms in driving the oxygen absorption, together with the role of antimony in enhancing the electrochemical performance toward the ORR, are discussed.

Role of antimony in the charge transport mechanisms for La0.67Ca0.33Mn1–xSbxO3 manganites

Single phasic La0.67Ca0.33Mn1–xSbxO3 (LCMSO; x = 0.00, 0.02, 0.04, 0.06, 0.08 and 0.10) samples were characterized by performing temperature and magnetic field dependent resistance measurements. Present study, mainly, aims for the better understanding of possible charge conduction mechanisms responsible for the low temperature resistivity and high temperature [well above metal to insulator transition temperature (TP)] semiconducting regions. Variation in resistivity and TP with Sb5+ content (x) and applied magnetic field has been discussed in the light of the modifications in structural and magnetic lattices of smaller diamagnetic Sb5+ doped LCMSO system. Various models and mechanisms have been theoretical employed to fit obtained experimental resistivity data for the low temperature resistivity and semiconducting regions of all LCMSO manganites. It is found that low temperature resistivity minima follows the coulomb blockade model while charge conduction in the semiconducting region obeys the variable range hopping (VRH) mechanism. Variation in low temperature blocking energy, activation energy in semiconducting region and magnetoresistance (MR) with Sb5+ content (x) and applied magnetic field has been discussed in detail.

Metal-Organic Framework-Derived NiSb Alloy Embedded in Carbon Hollow Spheres as Superior Lithium-Ion Battery Anodes.

The MOFs (metal-organic frameworks) have been extensively used for electrode materials due to their high surface area, permanent porosity, and hollow structure, but the role of antimony on the MOFs is unclear. In this work, we design the hollow spheres Ni-MOFs with SbCl3 to synthesize NiSb⊂CHSs (NiSb-embedded carbon hollow spheres) via simple annealing and galvanic replacement reactions. The NiSb⊂CHSs inherited the advantages of Ni-MOFs with hollow structure, high surface area, and permanent porosity, and the NiSb nanoparticles are coated by the formed carbon particles which could effectively solve the problem of vigorous volume changes during the Li+ insertion/extraction process. The porous and network structure could well provide an extremely reduced pathway for fast Li+ diffusion and electron transport and provide extra free space for alleviating the structural strain. The NiSb⊂CHSs with these features were used as Li-ion batteries for the first time and exhibited excellent cycling performance, high specific capacity, and great rate capability. When coupled with a nanostructure LiMn2O4 cathode, the NiSb⊂CHSs//LiMn2O4 full cell also characterized a high voltage operation of ≈3.5 V, high rate capability (210 mA h g-1 at a current density of 2000 mA g-1), and high Coulombic efficiency of approximate 99%, meeting the requirement for the increasing demand for improved energy devices.

Antimony (SbIII) reduces growth, declines photosynthesis, and modifies leaf tissue anatomy in sunflower (Helianthus annuus L.).

The role of antimony (Sb)--a non-essential trace metalloid--in physiological processes running in crops is still poorly understood. Present paper describes the effect of Sb tartrate (SbIII) on growth, Sb uptake, photosynthesis, photosynthetic pigments, and leaf tissue organization in young sunflower plants grown in hydroponics. We found that growth of below- and aboveground part was reduced with increasing concentration of Sb in the medium. Although Sb was mostly taken up by sunflower roots and only small part (1-2%) was translocated to the shoots, decline in photosynthesis, transpiration, and decreased content of photosynthetic pigments were observed. This indicates that despite relatively low mobility of Sb in root-shoot system, Sb in shoot noticeably modifies physiological status and reduced plant growth. Additionally, leaf anatomical changes indicated that Sb reduced the size of intercellular spaces and made leaf tissue more compact.

Role of antimony in the phase structure and electrical properties of potassium–sodium niobate lead-free ceramics

In the past ten years, antimony has been reported to strongly affect the developments in the piezoelectric properties of (K,Na)NbO3 (KNN) lead-free ceramics, that is, its enhanced piezoelectric activity is closely related to the doped antimony as well its content.

Conduction mechanism in undoped and antimony doped SnO2 based FSP gas sensors

The conduction mechanism in highly porous thick film SnO2 sensing layers, obtained by a direct deposition technique using FSP (flame spray pyrolysis) and the role of antimony (Sb) additives is investigated by simultaneous DC electrical resistance and work function changes measurements in various ambient atmospheres. The results have shown that the conduction mechanism changes according to the ambient atmosphere from a depletion layer controlled one to flat band situation and to an accumulation layer controlled one. In comparison to former studies performed on polycrystalline thick film layers, obtained from pre-processed powders, the measurements indicate that the grain size of the sensing material has a big influence on the conduction mechanism. In the case of undoped FSP-SnO2 sensors the studies showed that the grains are fully depleted in oxygen containing atmospheres. By increasing the number of free charge carriers in the bulk of the semiconductor, it was found that the addition of Sb changes the conduction mechanism dramatically. In contrast to the undoped material, there is a direct switch from a conduction mechanism controlled by the depletion layer to the degenerated semiconductor surface situation. Additionally, an initial upwards band bending is observed, even in the absence of atmospheric oxygen, which indicates a surface effect of Sb.

The role of antimony in modifying of Al-Si-Cu cast alloy

The microstructure evolution and the tensile strength changes of hypoeutectic AlSi6Cu4 cast alloy modified by AlSb10 (0 - 10 000 ppm) was systematically investigated. The samples were study without and after T6 heat treatment. Several types of etching were used, which includes standard black and white etching (0.5 % HF), colour etching by Weck-Al (for documentation the eutectic cells) and deep etching by HCl (for eutectic Si morphology study). The results show that the addition of Sb into AlSi6Cu4 cast alloy should act as a modifier, so it supposes to change the eutectic Si morphology. However, its effect as a modifier is not as significant as we have expected. Its effect was more inoculation and caused refinement of microstructure what has led to mechanical properties increasing. Refinement of microstructure could obviously improve the size and distribution of eutectic cells. The eutectic cells are refined significantly in a fully modified eutectic microstructure (more than 1 000 ppm Sb). It can be speculated that the stick-fibrous transition of eutectic Si morphology involving in impurity modification may be independent of the frequency and mode of eutectic nucleation.

The FTIR studies of SnO 2:Sb(ATO) films deposited by spray pyrolysis

Thin films of SnO 2:Sb were prepared by ultrasonic spray pyrolysis method. The role of antimony in the SnO 2 is demonstrated by FTIR. It is found that at low Sb concentrations, the Sb ions prefer to substitute Sn 4+ in form of Sb 5+. While beyond a certain Sb concentration, Sb ions start to be reduced to Sb 3+, which have a negative effect on carrier concentration that, in turn, affects the reflectivity of SnO 2:Sb films. The increased disorder of SnO 2 at high Sb concentration is also shown by FTIR. The discussion of carrier scattering suggests that the ionized impurity and/or neutral impurity scattering are the dominant scattering mechanisms.

The role of antimony on properties of widely varying GaInNAsSb compositions

Antimony has been used as a surfactant to improve the quality of GaInNAs∕GaAs quantum wells for long-wavelength optoelectronics. We demonstrate the importance of antimony as a reactive surfactant and the proper usage of it with dilute nitrides in order to tailor the properties of solar cell and laser devices. The effects of the addition of antimony to low indium concentration (∼8%) and low strain GaInNAs material (for 1.0eV solar cell applications) were investigated. It was assumed previously that adding antimony helped all GaInNAs alloys, but the validity of this was not previously tested. The addition of antimony to high indium concentration (∼32%) and high strain GaInNAs samples led to a dramatic improvement in optical quality and a widening of the growth window, while it led to a degradation in the low indium (low strain) composition samples. The addition of indium under constant antimony flux also improved the optical quality of the GaInNAs material. Variations in the indium and antimony compositions revealed a competition in atomic incorporation into the GaInNAsSb alloy. This interaction will be discussed. Increasing indium and/or strain confirmed the reactive surfactant properties of antimony on GaInNAsSb alloys.

Use of transmission electron microscopy in the characterization of GaInNAs(Sb) quantum well structures grown by molecular beam epitaxy

The quaternary GaInNAs alloy is a very promising material system for lasers in the 1.2–1.6 μm range with application in telecommunication fiber-optic networks. While good quality laser material has been demonstrated at 1.3 μm, pushing the emission beyond 1.5 μm by adding up to 40% In and 2% N has been unsuccessful. Recently, the addition of small amounts of Sb has put this alloy back on track for the 1.5 μm challenge by dramatically improving the luminescence efficiency of the material. In this work, high-resolution transmission electron microscopy (TEM), energy-filtered TEM, dark-field TEM, and energy-dispersive x-ray spectroscopy were used to structurally characterize both GaInNAs and GaInNAsSb quantum well structures. The results provide insight into the role of antimony in improving the optical properties of the material, namely reducing the local compositional fluctuations of In.

Structural Characterization of Molecular Beam Epitaxy Grown GaInNAs and GaInNAsSb Quantum Wells by Transmission Electron Microscopy

AbstractIn the past decade, the quaternary GaInNAs alloy has emerged as a very promising material for lasers in the 1.2-1.6 μm range with application in telecommunication fiber-optic networks. While most of the challenges in growing high quality laser material with emission wavelength out to 1.3 μm have been successfully resolved, extending the emission beyond 1.3 μm has proven to be quite difficult. Achieving emission out to 1.5 μm requires higher In (up to 40%) and N (up to 2%) compositions. This makes the growth of this thermodynamically unstable alloy quite difficult with phase segregation occurring even at lower growth temperatures. Recently, adding small amounts of antimony has dramatically improved the quality of the material and high luminescence has been demonstrated at wavelengths beyond 1.5 μm. In this study, high-resolution transmission electron microscopy (HRTEM) was used in a novel way in conjunction with dark-field (DF) TEM to elucidate the role of antimony in improving the material quality. The results show that antimony improves the material uniformity via reduction of the local compositional fluctuations of indium.

The structure of antimonian dussertite and the role of antimony in oxysalt minerals

Abstract The structure of antimonian dussertite, (AsO4)2(OH,H2O)6, has been refined in space group R3̄m with a 7.410(3), c 17.484(4) Å, Z = 3, to R = 3.2 % and Rw = 3.7 % using 377 observed reflections with I ≥ 3 σ(I). The structure is of the alunite-type and consists of sheets of corner-sharing (Fe3+,Sb5+)O6 octahedra parallel to (0001). The substitution of Sb5+ for Fe3+, and not for As5+, is unambiguously demonstrated not only by the structure refinement but also by electron microprobe analyses and crystal-chemical considerations. The icosahedrally coordinated Ba cations occupy cavities between pairs of octahedral sheets and are surrounded by six O atoms from the AsO4 tetrahedra and six O atoms from the (Fe3+,Sb5+)O6 octahedra. The mean bond lengths for the various coordination polyhedra are As-O 1.684(3) Å, (Fe,Sb)-O 2.004(1) Å, and Ba-O 2.872(2) Å. A hydrogen-bonding network is modelled using bond-valence calculations. The dussertite sample investigated is the first member of the crandallite group found to contain substantial Sb.

ChemInform Abstract: EFFECT OF ANTIMONY ON LEAD‐ACID BATTERY NEGATIVE

AbstractDie negative Elektrode einer Blei‐Säure‐Batterie hat eine Ladungsausb.

Effect of Antimony on Lead‐Acid Battery Negative

The role of antimony on the lead‐acid battery negative in terms of its effect on charge efficiency, its effect on gassing overpotential, its interactive influence with lignin expander in controlling the charge efficiency, and its retentive behavior or purging characteristics as in the overcharge gas stream was investigated. Linear potential sweep (LPS) cycling of Planté‐type lead electrodes was used to determine the effect of antimony and/or lignin expander on charge efficiency. Pasted‐type lead electrodes were used to determine the effect of antimony on gassing overpotential and to monitor its concentration either in the active material or the exit gas stream. Results showed a significant contribution of antimony in decreasing charge efficiency and an overwhelming role of lignin expander in suppressing the effect of antimony on charge efficiency. The critical lead‐electrode potential for purging antimony from the electrode is close to −1275 mV (vs. ).

The Role of Antimony in Positive Plate Behavior in the Lead‐Acid Cell

Antimonial and antimony‐free lead‐acid cells of similar construction were examined together in a shallow cycle routine. The presence of antimony in the positive grid alloy caused depolarization of the plate in the float condition. It did not affect the discharge potential of the plate. The positive plate active material became progressively softer in the antimony‐ free cells which failed after short test duration. The antimonial cell maintained its capacity and the active material remained firm. The active material of both successful and failing positive plates was examined by electron microscopy and x‐ray diffraction. The active material in the antimonial cell contained many complex prismatic crystals, whereas the antimony‐free cell was characterized by nondescript nodular masses. The active material in. the antimonial cell contained a large amount of while the antimony‐free positive contained very little of this polymorph. Because both kinds of cell were pasted and formed by the same manufacturer with the same paste formulation, it is concluded that the difference in paste morphology and composition is caused by the presence of antimony in the positive grid. It is also concluded that success or failure in float cycle tests is determined by the morphology of the positive paste.

The role of antimony in tropical medicine

The role of antimony in tropical medicine