Three kinds of dialkylphosphinic acids (DAPAs), i.e. dihexylphophinic acid (DHPA), di-(2,4,4-trimethylpentyl) phosphinic acid (DTMPPA) and didecylphophinic acid (DDPA), were synthesized through free radical addition reaction. The influence of the types of initiator, reation time and reaction temperature on the yield of DAPAs were investigated. The products were characterized by NMR and MS. By using DHPA, DTMPPA and DDPA (10% in kerosene) as extractants, the extraction of Co²⁺ and Ni²⁺ in sulphate medium at different equilibrium pH values were measured. The results show that the maximum yield of DHPA, DTMPPA and DDPA can all be achieved at about 130 ℃ under the initiation of di-tert-butyl peroxide (DTBP). All the extraction of cobalt with respect to DHPA, DDPA and DTMPPA precedes that of nickel. The difference in pH_1/2 value (defined as the pH at which 50% metal extraction occurs) between cobalt and nickel increases in the following sequence from large to small: DHPA, DDPA and DTMPPA, which indicates that the separation ability for cobalt and nickel ascends from DHPA, DDPA to DTMPPA.

A novel and simple solid-liquid chemical reaction route was proposed to synthesize ZnS nanoparticles. In the method, ZnS nanoparticles were prepared by reaction of ZnO and Na₂S in water with ultrasonic radiation at low temperature. The effects of process parameters on the properties of ZnS particles were investigated. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared spectroscopy (IR), thermogravimetry- differential thermogravimetry (TG-DTG) and fluorescence emission spectroscopy. The results show that these particles are good crystalline zinc blende with average size of 35 nm, and possess good IR transmittance in the range of 400 to 4 000 cm⁻¹ and good thermal stability in oxygen.

Four shapes of Cu₂O particles as sphere, cube, truncated octahedron and octahedron were prepared via glucose reduction of Cu(Ⅱ) under alkaline condition. The products were characterized by XRD and SEM. The effects of the precursor (CuO, Cu(OH)₂), reaction temperature and glucose concentration on morphology of Cu₂O particles were investigated, and the mechanism of morphology control was discussed on the basic theory of crystal nucleation and growth. It is found that the Cu⁺ supersaturation is remarkably influenced by the precursor kind, reaction temperature and glucose concentration, and the morphology of Cu₂O particles can be controlled by the Cu⁺ supersaturation.

Boehmites (Al₂O₃·xH₂O) were hydrothermally prepared from aluminum alkoxide. The effect of temperature on preparation was studied in the range of 100−180 ℃. The XRD analysis shows that with temperature increasing, the transformation of pseudo-boehmite into well-crystallized boehmite takes place. The micro-morphologies change also from irregular clew to thin cubic platelets. From the mass loss of the samples prepared at different temperatures, the value of x is estimated to vary between 1.06 and 1.67. γ-Al₂O₃ obtained by subsequent calcination of boehmite at 600 ℃ is also characterized by XRD and its morphology remains unchanged.

Fe-Ni alloy coatings were electrodeposited on ferritic stainless steel (FSS) in solutions containing FeSO₄ and NiSO₄. The effects of pH, [Fe²⁺]/[Ni²⁺] (molar ratio) of electroplating solutions and cathode current density on deposition rate and surface appearances of the coatings were investigated. The results indicated that the deposition rate of the coating in solution with [Fe²⁺]/[Ni²⁺] of 0.4 slightly increased with increasing pH from 2.5 to 3.5 under the current density of 5.5 mA/cm², and then the deposition rate of the coating in solution with pH 4.0 began to decrease. The deposition rate also slightly increased with pH up to 3.5 under higher cathode current densities of 13.5 and 27 mA/cm². Under 13.5 mA/cm², however, the coating deposited in solution with pH 4 was prone to crack or flake. The deposition rate increased and the surface of coatings became less smooth with increasing cathode current density. The effect of the ratio of [Fe²⁺] to [Ni²⁺] on deposition rate was not obvious. With increasing the ratio of [Fe²⁺] to [Ni²⁺] in plating solution, the content of Fe in the coatings increased; while the Ni content in the coatings decreased with the increase in the ratio of [Fe²⁺] to [Ni²⁺]. The deposited coating consisted of Fe-Ni alloy phase.
附件:43-p226

A microemulsion-mediated hydrothermal method for synthesis of YVO₄׃RE (RE=Yb³⁺/Er³⁺, Yb³⁺/Tm³⁺) nanoparticles by hydrothermal treatment of quaternary microemulsion medium consisting of Na₃VO₄/NaOH and RE(NO₃)₃ aqueous solution，surfactant cetyltrimethylammonium bromide (CTAB), cosurfactant n-hexanol and oil phase n-heptane was report. The confinement of microemulsion droplets acting as microreactors during the reaction process allows the formation of small size YVO₄׃RE nanoparticles with relatively narrow size distribution and less aggregation. The structure, size and shape of YVO₄׃RE nanoparticles were investigated by means of X-ray diffractometry (XRD) and transmission electron microscopy (TEM). Compared with the conventional solid annealing diffusion method, the microemulsion-mediated hydrothermal method shows superiority in obtaining YVO₄׃RE nanoparticles with controllable size, narrow size distribution and less aggregation. The microemulsion-mediated hydrothermal method may be potentially applicable for synthesis of other rare earth doped up-converting luminescence nanomaterials.

With Zinc acetate and sodium hydroxide as raw materials, while polyethylene glycol employed as dispersant agent, ultrafine zinc oxide powder was synthesized by hydrothermal method. Influence of NaOH concentration on morphology of ZnO powder was studied. The as-synthesized ZnO powder looked like flower cluster and consisted of microrods with hexagonal morphologies. The crystal structure and optical property of the as-prepared powder were also characterized using XRD, UV-visible absorption spectrum and photoluminescence spectrum. The results indicate that ZnO powder is of hexagonal wurtzite structure and well crystallized with high purity. There is a strong excitation absorption peak at 300 nm in UV-visible absorption spectrum and blue shift exists obviously. The optical property of ZnO powder is excellent.

High dispersive copper nanoparticles were prepared by chemical reduction method using potassium borohydride as reducing agent. The effects of reactant ratio, concentration of CuSO₄, reaction temperature, and dispersant on the size of product and conversion rate were studied. The morphologies of copper nanoparticles were characterized by scanning electron microscopy. The results show that the optimum process conditions are as follows: the molar ratio of KBH₄ to CuSO₄ is 0.75 (3׃4), concentration of CuSO₄ is 0.4 mol/L, reaction temperature is 30 ℃, and dispersant is n-butyl alcohol. The average particles size of copper powders with spherical shape gained is about 100 nm.

An ionic liquid was prepared by mixing AlCl₃ and 1-methyl-3-ethylimidazolum bromide (EMIM)Br under dry argon atmosphere. Electrodeposition of aluminum on magnesium was conducted at 298.15 K for 1 h by the ionic liquid and the electrochemical behavior was discussed. The results show that the aluminium deposition occurs at a potential about −0.1 V. Cathode surface was analyzed by SEM, XRD and EDS. Aluminum is successfully electrodeposited on magnesium from (EMIM)Br-AlC1₃ ionic liquid, and the crystal grain quality of the deposit at 15 mA/cm² is ideal with the perfect boundary of crystal grain.

Nickel hydroxide doped with multi-wall carbon nanotubes (MCNTs) was synthesized by chemical coprecipitation method. The MCNTs doped nickel hydroxide was used as the electrochemical active material in the positive electrodes of rechargeable alkaline batteries. The powder X-ray diffraction (XRD) analysis shows that the addition of MCNTs induces more structural defect within the crystal lattice of the nickel hydroxide. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests demonstrate the better reaction reversibility and lower electrochemical impedance of MCNTs doped nickel hydroxide as compared with the pure nickel hydroxide. The charge/discharge tests show that MCNTs addition can improve the specific discharge capacity and increase the discharge voltage of the nickel hydroxide electrode.

Chemical reduction method was employed to prepare nano-sized Sn₂SbNi alloy composites used as anode material for rechargeable lithium ion batteries. This strategy was adopted to combine the virtues of both active/inactive and active/active alloys to fabricate a Sn₂SbNi alloy powder with two active components and one inactive component. The two active components can realize the high capacity feature of electrode and can make the volume change of electrode take place in a stepwise manner due to the different lithiation potentials of two active components, leading to a stable cycling performance. Sn₂SbNi alloy provides a reversible specific capacity over 640 mA∙h/g with an excellent cyclic ability. The Sn-Sb-Ni alloy composite material shows to be a good candidate anode material for the lithium ion batteries.

LiMn₂O₄/Li₄Ti₅O₁₂ composite was synthesized by in-situ composite technique using LiMn₂O₄, lithium acetate, tetrabutyl titanate as starting materials and characterized by various electrochemical methods in combination with X-ray diffractometry (XRD), infrared (IR) spectroscopy and scanning electron microscopy (SEM). The results show that Li₄Ti₅O₁₂ is coated on the surface of crystalline LiMn₂O₄ to form LiMn₂O₄/Li₄Ti₅O₁₂ composite. The structure of LiMn₂O₄ does not change due to the introduction of Li₄Ti₅O_12. By being coated with Li₄Ti₅O₁₂, the rate capability and high temperature cyclability of LiMn₂O₄ is improved greatly. At room temperature, the discharge capacity of LiMn₂O₄/Li₄Ti₅O₁₂ composite is more than 108.4 mA∙h/g and the capacity loss per cycle is only 0.053% after 20 cycles at 2.0C.While at 55 ℃, the discharge capacity of LiMn₂O₄/Li₄Ti₅O₁₂ composite is more than 109.9 mA∙h/g and the capacity loss per cycle is only 0.036% after 60 cycles at 1.0C.

Li₄Ti₅O₁₂ powders were prepared by so-gel method using tetrabutyl titanate, lithium acetate and absolute alcohol as starting materials. Li₄Ti₅O₁₂-polyaniline (Li₄Ti₅O₁₂-PAn) composite was prepared by in situ polymerization method using aniline, ammonium persulfate and hydrochloricarried as starting materials. Li₄Ti₅O₁₂-PAn composite was characterized by X-ray diffractometry (XRD), infrared spectrum (IR) combined with electrochemical tests. The results show that the electrical conductivity is enhanced obviously due to the introduction of PAn to Li₄Ti₅O₁₂. Li₄Ti₅O₁₂-PAn composite exhibits better high-rate capability and cyclability than Li₄Ti₅O₁₂. The composite can deliver a specific capacity of 191.3 and 148.9 mA∙h/g, only 0.13% and 0.61% of the capacity is lose after being discharged 80 times at 0.1C and 2.0C, respectively.

SnO₂-Li₄Ti₅O₁₂ was prepared by sol-gel method using tin tetrachloride, lithium acetate, tetrabutylorthotitanate and aqueous ammonia as starting materials. The composite was characterized by thermogravimertric (TG) analysis and differential thermal analysis (DTA), X-ray diffractometry (XRD) and transmission electron microscopy (TEM) combined with electrochemical tests. The results show that SnO₂-Li₄Ti₅O₁₂ composite derived by sol-gel technique is a nanocomposite with core-shell structure, and the amorphous Li₄Ti₅O₁₂ layer with 20−40 nm in thickness is coated on the surface of SnO₂ particles. Electrochemical tests show that SnO₂-Li₄Ti₅O₁₂ composite delivers a reversible capacity of 688.7 mA∙h/g at 0.1C and 93.4% of that is retained after 60 cycles at 0.2C. The amorphous Li₄Ti₅O₁₂ in composite can accommodate the volume change of SnO₂ electrode and prevent the small and active Sn particles from aggregating into larger and inactive Sn clusters during the cycling effectively, and enhance the cycling stability of SnO₂ electrode significantly.

Metatitanic acid was synthesized from industrial titanyl sulfate solution via controlling pH during hydrolyzing process. Inductively coupled plasma (ICP) analysis confirmed that a little Fe, Mg and Ca were deposited into precursor TiO₂·H₂O. Spinel Li₄Ti₅O₁₂ was prepared by sintering amorphous mixture at 800 ℃ for 16 h. The amorphous mixture was activated by ball-milling at room temperature, using the as-prepared TiO₂·H₂O and Li₂CO₃ as raw materials. The sample was characterized by X-ray diffractometry, scanning electron microscopy and electrochemical charge and discharge test. The results show that spinel Li₄Ti₅O₁₂ is obtained, but it contains a few rutile TiO₂ impurities. The sample has fine particles with size of around 50 nm and homogenous size distribution. At room temperature, the initial reversible specific capacity of the sample is 136.9, 128.0, 119.2 and 96.3 mA·h/g at 0.1C, 1C, 2C and 5C, respectively, and the sample shows excellent cycling performance.

LiVPO₄F was synthesized by a novel sol-gel method under Ar atmosphere using V₂O₅·nH₂O, LiF, NH₄H₂PO₄, and citric acid as starting materials, and its physicochemical properties were characterized using X-ray diffractometry (XRD), SEM, and electrochemical methods. The XRD patterns show that LiVPO₄F displays a triclinic structure with a space group of . The SEM results indicate that the particle size of LiVPO₄F is about 0.8 µm together with homogenous distribution. The optimal sintering temperature and sintering time are 600 ℃ and 20 h, respectively, in order to obtain pure triclinic LiVPO₄F with good electrochemical performance. LiVPO₄F has the discharge capacity of 134 mA∙h/g in the range of 3.0−4.4 V at the first cycle, and the discharge capacity remains 125 mA∙h/g after 30 cycles. The sol-gel method is suitable for the preparation of LiVPO₄F cathode materials with good electrochemical performance for lithium ion batteries.

LiNi_0.8Co_0.1Mn_0.1O₂ was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement, electron scanning microscopy and electrochemical measurements. Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi_0.8Co_0.1Mn_0.1O₂ were also investigated. The results show that the sample synthesized at 750 ℃ with 105% lithium content has fine particle sizes around 200 nm and homogenous sizes distribution. The initial discharge capacity for the powder is 184 mA∙h/g between 2.7 and 4.3 V at 0.1C and room temperature.

In order to obtain substrates with good conductive foam for high porosity foam metal materials used in the metal electrodes, the technique of electroless copper plating on the microcellular polyurethane foam with pore size of 0.3 mm was investigated. The main factors affecting the deposition rate such as the solution composition, temperature, pH value and adding ultrasonic were explored. The results show that the optimum process conditions are CuSO₄ 16 g/L, HCHO 5 mL/L, NaKC₄H₄O₆ 30 g/L, Na₂EDTA 20 g/L, K₄Fe(CN)₆ 25 mg/L, pH value of 12.5−13.0 and temperature of 40−50 ℃. Under these technical conditions, the process has excellent bath stability. Adding ultrasonic on the process can elevate the deposition rate of copper by 20%−30%. The foam metal material with a porosity of 92.2% and a three-dimensional network structure, was fabricated by electro-deposition after the electroless copper plating.

Polyaniline (Pani) anode is tested to highlight the feasibility of reduction of both energy consumption and capital costs in zinc electrowinning from sulfate solution without any modification to the existing plant. Current density, electrolyte temperature, added gelatin, added Mn²⁺, oxygen-evolution potential, cell potential and long duration tests were investigated. The zinc deposits were also studied by means of scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that current density and added gelatin change the preferred crystal orientations of the zinc deposits. Compared with Pb-Ag(1%) anode used in industry, the cell voltage decreases by 0.15−0.30 V, energy consumption of Zn is 2.46−2.70 kW∙h/kg which results in 20% energy savings. Long duration tests show that Pani anode can represent a good alterative ability for zinc electrowinning. Zinc deposits obtained have no Pb pollution. The additions of Mn²⁺ ions and gelatin also change the surface morphology and deposit quality of the electrodeposited zinc, affecting the crystal orientation. These researches demonstrate that Pani anode has distinct advantages over acidic electrowinning process.

Using Donnan Steric Partitioning Model (DSPM), the data for the rejection of four salts having common co-ion (LiCl, NaCl, KCl, Na₂SO₄) were obtained and they show the characters of the polyethersulfone (PES) nanofiltration (NF) membrane in terms of three parameters: an effective pore radius (r_p), the ratio of effective thickness over porosity (λ/A_k) and an effective charge density (X). Good agreement between experimental data and prediction data using the three parameters mentioned above was obtained. A theoretical model was developed to predict the transport performance of electrolyte through the hollow fiber composite NF membrane. The model prediction is in good agreement with experimental results based on the method by modern numerical solution.