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Olivine structure LiFe1−xVxPO4/C (x = 0.02, 0.04, 0.06) composite materials as the cathode for lithium ion batteries were synthesized by carbon-thermal reduction method, using Fe(NO3)3 · 9H2O, LiH2PO4, NH4VO3, and C6H12O6 (glucose) as raw materials. The X-ray diffraction (XRD), scanning electronic microscope (SEM) laser particle size analysis, specific surface area tester, and electrochemical performance testing were used to study its structure, morphology, and electrochemical properties. The results showed that the diffraction peaks of the prepared materials correspond to the single phase of LiFePO4/C and can be indexed as the olivine structure. Particle diameter of LiFe1−xVxPO4/C (x = 0.04) was uniform. Specific surface areas of materials are all increased. An electrochemical test showed that LiFe1−xVxPO4/C (x = 0.04) demonstrated a better electrochemical capacity of 141.065 mAh · g−1 at 0.1C rate, and which had an increase of 10.77% than the un-doped sample. After 20 cycles, charge and discharge specific capacity almost had no attenuation. [ABSTRACT FROM AUTHOR]

In this paper, the electrochemical deposition was used to form calcium phosphate/chitosan (Ca-P/chitosan) membranes on the surface of AZ91D magnesium alloy coated with a microarc oxidization (MAO) membrane. The surface appearance, chemical compositions, and crystalline structures of the Ca-P/chitosan membranes were detected by using scanning electron microscope (SEM), X-ray diffractometer (XRD), and energy-dispersive spectroscopy (EDS). They showed that the surface morphology of the membranes had a remarkable modification after introducing chitosan to Ca-P membrane, and the binding force was distinctly increased between the metal substrate and the membrane. The composite membranes were composed of Tricalcium Phosphate (TCP), Dibasic Calcium Phosphate (DCP), and Hydroxyapatite (HAP). Immersion was tested in simulated body fluid (SBF) and the corrosion resistance of the membranes was evaluated by electrochemical measurements. Results exhibit the composite membranes have low corrosion rate and superior stability. [ABSTRACT FROM AUTHOR]

In this paper, Cu coated carbon fibers were prepared using the electroless plating method. Effects of pretreatment, dispersing capability, formaldehyde, temperature, and pH on electroless plating process were studied. The connection between the Cu2+concentration in the electroless plating solution and the plating time at different temperatures was studied. The process of the electroless Cu plating was analyzed and calculated, which derived the activation energy of the electroless copper plating on carbon fibers:Ea = 32.68 kJ/mol. The effect of the mass of carbon fibers and Cu coated carbon fibers which were dispersed in 80 mL distilled water on the conductivity of the solution was also studied. And as a result, the conductivity of the solution increased with the amount increasing. However, when the amount of the fibers was more than 0.08 g, the fibers would be incompletely dispersed. Thus, it could be concluded that the best accession amount of carbon fibers in 80 mL distilled water was 0.08 g. The corresponding conductivity values of carbon fibers and copper-coated fibers were 12.5 and 20.5 µs/cm, respectively. [ABSTRACT FROM AUTHOR]