Thermoelectric Properties of Silver Antimonate with Mixed Valency of Antimony

Silver (Ag) and silver antimonate (AgSbO3) composites with different amounts of Sb3+ were synthesized by normal sintering with the aim of realizing a thermoelectric material. The electrical conductivity (σ) increased in the sample containing larger amount of Sb3+, whereas Seebeck coefficient (S) decreased. Producing Sb3+ caused the generation of oxygen vacancies in the material, and thus the corresponding donor levels are created in the bandgap, providing more conduction electrons. The conductive Ag particles would contribute to the conduction path as bypasses for carrier transport. The thermal conductivity (κ) was slightly lower in the presence of Ag defects in AgSbO3.

Acid-stable antimonate based catalysts for the electrocatalytic oxygen evolution reaction

Acid-stable and highly active catalysts for the electrocatalytic oxygen evolution reaction(OER)are paramount to the advancement of electrochemical technologies for clean energy conversion and utilization.In this work,based on the density functional theory(DFT)calculations,we systematically investigated the MSb_(2)O_(6)(M=Fe,Co,and Ni)and transition metal(TM)doped MSb_(2)O_(6)(TM-MSb_(2)O_(6),TM=Mn,Fe,Co,Ni,Cu,Zn,Ru,Rh,Pd,Ir,and Pt)as potential antimonate-based electrocatalysts for the OER.The stability and OER activity of these considered electrocatalysts were systematically studied under acidic conditions.It was found that Rh-NiSb_(2)O_(6),Pt-CoSb_(2)O_(6),Rh-FeSbO4,and Co-NiSb_(2)O_(6)can serve as efficient and stable OER electrocatalysts,and their OER catalytic activities are better than that of the current state-of-the-art OER catalyst(IrO2).Our findings highlight a family of promising antimonate-based OER electrocatalysts for future experimental verification.

Removal of antimonite and antimonate from water using Fe-based metal-organic frameworks: The relationship between framework structure and adsorption performance

We investigated the adsorption performance of five Fe-based MOFs(Fe-BTC,MIL-100(Fe),MIL-101(Fe),MIL-53(Fe)and MIL-88 C(Fe))for removal of antimonite(Sb(Ⅲ))and antimonate(Sb(Ⅴ))from water.Among these MOFs,MIL-101(Fe)exhibited the best adsorption capacities for both Sb(Ⅲ)and Sb(Ⅴ)(151.8 and 472.8 mg/g,respectively)which were higher than those of most adsorbents previously reported.The effect of steric hindrance was evident during Sb removal using the Fe-based MOFs,and the proper diameter of the smallest cage windows/channels should be considered an important parameter during the evaluation and selection of MOFs.Additionally,the adsorption capacities of MIL-101(Fe)for Sb(Ⅴ)decreased with increasing initial p H values(from 3.0 to 8.0),while the opposite trend was observed for Sb(Ⅲ).Chloride,nitrate and sulfate ions had a negligible influence on Sb(Ⅴ)adsorption,while NO3-and SO42-improved Sb(Ⅲ)adsorption.This result implies that inner sphere complexes might form during both Sb(Ⅲ)and Sb(Ⅴ)adsorption.

Role of Sb(V) in removal of As, Sb and Bi impurities from copper electrolyte

The function mechanism of Sb（V） in As, Sb and Bi impurities removal from copper electrolyte was investigated by adding Sb（V） ion in a synthetic copper electrolyte containing 45 g/L Cu2＋, 185 g/L H2SO4, 10 g/L As and 0.5 g/L Bi. The electrolyte was filtered, and the precipitate structure, morphology and composition were characterized by chemical analysis, SEM, TEM, EDS, XRD and FTIR. The results show that the precipitate is in the shape of many irregular lumps with size of 50-200 μm, and it mainly consists of As, Sb, Bi and O elements. The main characteristic bands in the FTIR spectra of the precipitate are As-O-As, As-O-Sb, Sb-O-Bi, Sb-O-Sb and Bi-O-Bi. The precipitate is the mixture of microcrystalline of AsSbO4, BiSbO4 and Bi3SbO7 by XRD and electronic diffraction. The removal of As, Sb and Bi impurities by Sb（V） ion can be mainly ascribed to the formation of antimonate in copper electrolytes.

Aqueous-Phase Sorption Behaviors of Cs⁺, Co²⁺, Sr²⁺and Cd²⁺ions on some Composite Ion Exchangers

A two new hybrid “organic-inorganic” composite ion exchangers (SAM and FAM), was synthesized by the combination of inorganic ion exchanger tin (IV) silicate and tin (IV) antimonate respectively with organic polymer polyacrylamide (PAm). The sorption isotherms for Cs+, Co2+, Sr2+ and Cd2+ ions on composite ion exchanger were investigated in the range (0.0005 - 0.01M) at different reaction temperature (30℃, 45℃ and 60℃ ± 1℃). The sorption data were subjected to different sorption isotherms and the results verified that Langmuir isotherm is the best model to be applied, and the monolayer sorption capacity were calculated and was found to increase as the reaction temperature increases.

Structure of V_2O_5-P_2O_5-Sb_2O_3-Bi_2O_3 glass

The structure ofV2O5-P2O5-Sb2O3-Bi2O3glass and its state of crystallization were studied by means of infrared spectroscopy and X-ray diffraction analysis. The results indicate that, in this glass, V and P exist mainly in the form of a single-stranded linear （VO3）n and an isolated （PO4） tetrahedral with no double bond. Partial V and P are connected through O, forming an amorphous structure of layered vana- dium phosphate. Trivalent Sb3＋ and Bi3＋ open the V=O bond and appear in interlayers, so a weak three-dimensional structure is connected successfully. Along with the substitution of Sb203 for partial V205 or that of P205 for partial V205, the network structure of the glass is rein- forced, and the crystallization is reduced.

Synthesis and characterization of arsenate antimonic acid AAAc(1 : 1)

The AAAc(1 : 1) was synthesized in water by As2O3 and Sb2O3 with molar ratio of 1 : 1: AAAc(1 : 1)was characterized by Raman, IR, TG/DTG, DSC, XPS and XRD. The results show that there are four peaks to vsof As-OH, As-O-Sb, Sb-OH and Sb-O-Sb in Raman spectra of AAAc(1 : 1) at 100 - 1 000 cm-1. The solution of AAAc(1 : 1) was also titrated with KOH solution. The titration results show that AAAc(1 : 1) is a hexabasic acid with dissociation constants of k1 = 3.62 × 10-2 , k2 = 3.05 × 10-3 , k3 = 6. 43 × 10-6 , k4 = 9. 78 × 10-8 ,k5 = 1.32 × 10-11 , k6 =3.87 × 10-12. AAAc(1 : 1) has a good solubility and stability in water, its solid obtained by free volatilizing water from its solution under air at ambient temperature is amorphous. Chemical and thermal analyture of AsO ( OH )2-OH-Sb ( OH )4-O-Sb ( OH )4-OH-AsO ( OH )2 or As ( OH )3-O-Sb(OH)4-O-Sb(OH)4-O-As(OH)3 (isomerism) through experimental determination and geometry optimization.

Spectral properties and Judd-Ofelt analysis of novel red phosphors Gd_(2)InSbO_(7):Eu^(3+)with high color purity for white LEDs

Gd_(2)InSbO_(7):Eu^(3+)red phosphors we re successfully synthesized via high-temperature solid-state reactio n.The phase purity,particle size,and luminescence properties of obtained phosphors were measured and analyzed in detail.The Gd_(2)InSbO_(7)lattice possesses cubic structure with F_(d-3 m)(227)space group.The phosphors emit bright red emission at 628 nm under 393 nm excitation,and this phenomenon is attributed to the^(5)D0-^(7)F_(2)transition.The Judd-Ofelt parameters(Ω_(2),Ω_(4)),transition ratio,and branching ratios(β)of Eu^(3+)-doped Gd_(2)InSbO_(7)phosphor were calculated on the basis of the emission spectra and decay lifetimes.The optimal content in Gd_(2)InSbO_(7):xEu^(3+)is identified to be 15 mol%.The thermal quenching of Gd_(2)InSbO_(7):Eu^(3+)is found to be over 500 K,and its activation energy is 0.26 eV.The Commission Internationale de l’Eclairage(CIE)chromaticity coordinates of Gd_(2)InSbO_(7):15%Eu^(3+)are(0.629,0.371),which are close to ideal red chromaticity coordinates(0.670,0.330).The fabricated w-LED exhibits good color rendering index(Ra)(86),correlated color temperature(CCT)(6997 K),and CIE chromaticity coordinates(0.302,0.330).The obtained results demonstrate that Gd_(2)InSbO_(7):Eu^(3+)phosphors have potential applications in white LEDs.

Synthesis and Electrochemical Properties of FeSbO_4 Nanorods

Well-crystallized FeSbO 4 nanorods with rutile-like structure are synthesized through a solid-state reaction and used as cathode material of Li-ion battery for the first time.The obtained nanorods can react with 11 Li-ions per FeSbO 4 unit with a specific discharge capacity of 1 100 1 mAh g between 0.1 and 2.0 V.Three discharge plateaus can be observed during the fully discharging process,but the reversible reaction with 1 Li occurs between 1.5 V and 4.5 V vs.Li ＋ /Li,and the reversible capacity is only 50-80 1 mAh g.FeSbO 4 nanorods have a stable cyclic performance between 1.5 V and 4.5 V and it can be used as cathode material for rechargeable Li-ion battery.