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For extraction of metallic lanthanum from molten NaCl-CsCl-LaCl3 solutions, the electrochemical reduction of La(III) ions on inert Mo and liquid Ga electrodes were explored. Transient electrochemical techniques have been used to explore the reduction mechanism, transport parameters and thermodynamics properties. The obtained results indicate that the electrochemical reaction of La(III) + 3ē → La on inert electrode is a single-stage irreversible process, which controlled by the charge transfer rate. Simultaneously, the diffusion coefficient of [LaCl6]3− complex ions was obtained at different temperatures. The apparent standard potentials of La3+/La couple and La-Ga alloy vs the temperature were determined. The base thermodynamic properties of lanthanum compounds were calculated. Furthermore, the potentiostatic method of electrolysis was used for the synthesis of La-Ga alloys.

Anhydrous K3YbCl6 was obtained via solid-phase reaction from Yb2O3 with NH4Cl and KCl as chlorination agents. Electrochemical behaviour of ytterbium ions was investigated in LiCl–KCl–MgCl2–K3YbCl6 melt at 903 K on W electrodes. The signal corresponding to Mg2Yb intermetallic compound was detected at the potential close to that of the formation of Mg–Li alloy. Bulk Mg–Li–Yb alloys, characterized by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM), were prepared via electrochemical co-reduction of Mg, Li and Yb on W electrodes. Yb-rich Mg–Li–Yb alloys with different constituents were obtained via the change of the concentration of K3YbCl6.

In current work, vanidium-substituted polyoxometalate clusters H8P2Mo16V2O62 and carbon nanotubes (CNTs)@Au NPs were incorporated into a multilayer composite film via combining layer-by-layer self-assembly. The result showed that the incorporation of the three kinds of active components would improve the electrocatalytic activity to the oxidation of FA and electron transfer rate greatly. In 0.2 M phosphate buffer solution (pH = 7.35), the composite film (PEI/P2Mo16V2/PEI/CNTs@Au)2 had a linear range of FA from 4.99 × 10-7 M to 1.29 × 10-5 M and 1.29 × 10-5 M to 1.21 × 10-3 M, and a limit of detection to be 3.96 × 10-8 M (S/N = 3). In addition, the composite film has an excellent anti-interference property to potential co-exist interfering species like inorganic ions and biomolecules (including NaCl, K2CO3, NH4Cl, NaNO2, Na2SO4, fructose, L-glutamate and glucose). The developed sensor has a good working and long-term stability as well. Besides, the sensor was applied in detecting FA in vitamin b tablet, the recoveries were all in the allowable error range. (This paper is funded by the International Exchange Program of Harbin Engineering University for Innovation-oriented Talents Cultivation.) Figure 1

The ionic liquid is a kind of ionic salt capable of being liquid state at room temperature. As a new type of green organic solvent, ionic liquid has the advantages of good electrical conductivity, wide electrochemical window, very low vapor pressure, and is widely used in electrochemical, organic synthesis and other fields. The use of ionic liquids as electrolytes in electrochemical oxygen sensors can alter the shortcomings of the current sensor's inability to operate at high temperature and humidity conditions. Besides, ionic liquids with certain catalytic functional group could improve the response performance of sensing devices. Therefore, in this paper, ionic liquids based on imidazolium, 1-methyl-3-propanesulfonic acid imidazolium hydrogensulfate ([Psmim]HSO4) and 1-methyl-3-butpropanesulfonic acid imidazolium hydrogensulfate ([Bsmim]HSO4 )with sulfonic-acid catalytic functional group were studied. Both ionic liquids mentioned above were synthesized through a traditional two-step method. Electrochemical tests including linear scanning voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) of both ionic liquids were carried out with an electrochemical workstation to characterize the intrinsic electrochemical performance of both ionic liquids. On the other hand, cyclic voltammetry (CV) curves were tested, which shows a proportional linear relationship between oxygen reduction peak current and the oxygen concentrations from 0% to 100% O2 with the corresponding R2 (R2 >0.97), and chronoamperometric current tsests were also carried out to futher confirm the ionic liquids promising materials for oxygen sensing. (This paper is funded by the International Exchange Program of Harbin Engineering University for Innovation-oriented Talents Cultivation.)

A large superficial (60×60cm) and high performance self-humidifying Pt-PFSA membrane for H2/Air polymer electrolyte membrane (PEM) fuel cells has been developed. The homemade Pt-PSFA composite membrane is prepared with solution-cast method by dispersing Pt black particles into the perfluorosulfonic acid (PFSA) copolymer resin uniformly. Electrochemical performances of the self-humidifying Pt-PFSA membrane and PFSA membrane compared in 150cm2 single cells with 0.6mg/cm2 platinum loading. The results indicated that Pt distribution in the Pt-PFSA composite membrane and the peak power density of the single cell reached over 37.8W at 60°, 0.05MPa with dry hydrogen and dry Air.

Gd2MoO6:Eu3+ nanofibers and nanobelts have been prepared by a combination method of the sol-gel process and electrospinning. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy, photoluminescence, and low voltage cathodoluminescence as well as kinetic decays were used to characterize the resulting samples. The results of XRD and FTIR indicate that the Gd2MoO6:Eu3+ samples have crystallized at 600 degrees C with the monoclinic (alpha) structure. The SEM and TEM results indicate that the as-formed precursor fibers and belts are uniform and that the as-prepared nanofibers and nanobelts consist of nanoparticles. Gd2MoO6:Eu3+ phosphors show their strong characteristic emission under UV excitation (353 nm) and low voltage electron-beam excitation (3 kV), making the materials have potential applications in fluorescent lamps and field-emission displays.

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Nanostructured composite materials with α-Ni(OH)2 loaded on multiwalled carbon nanotubes (MWNTS) of different mass (5wt%, 10wt%, 20wt%) were synthesized by homogeneous liquid-phase process and anealed at 300°C. Power X-ray diffraction (XRD), Thermogravimetric and differential scanning calorimetry (DG- DSC were applied to investigate the thermal behavior, crystalline structural. Their voltammery characteristics, galvanostatic discharge and AC impedance spectroscopy were carried out in three-electrode mode composite electrodes. A specific capacitance approximately to 229F/g could be achieved with NiO/MWNTS (10wt%) in the range of 0.27~0.5v in 2M KOH electrolyte. The NiO loaded on MWNTS was significantly improved the electrical conductivity and the active sites for redox reaction of metal oxide due to increasing its specific surface area by MWNTS.