Abstract: The series of powders with the general formula of Ce0.8-xZrxLa0.2O1.9 (x=0, 0.05, 0.10, 0.15) and
Ce0.8-xZrxY0.2O1.9 (x=0, 0.05, 0.10, 0.15) were synthesized by the sol-gel method. The samples sintered at
1500°C all possess the single phase with cubic fluorite structure. The lattice parameter and the ionic
conductivity decrease with increasing the content of Zr. However, the ionic conductivity of ceria
co-doped with Zr and La reduces with decreasing the lattice strain.
Abstract: Pr2O3-doped ceria nanopowders were synthesized by a nitrate-citrate combustion process. This
route is based on the gelling of nitrate solutions by the addition of citric acid and ammonium hydroxide,
followed by an intense combustion process due to an exothermic redox reaction between nitrate and
citrate ions. XRD analysis showed that no impurity were observed up to x=0.3 in Ce1-xPrxO2-δ systems.
The influence of ignition temperature on the characteristics of the powders was studied. The change of the
crystal structure with the content of doped Pr was investigated. The highest ionic conductivity,
σ600°C=2.45×10-3S/cm, was found for the composition of x=0.15.
Abstract: Ni-BaCe0.9Y0.1O3-δ mixed protonic-electronic conductor can be used to separate hydrogen from
syngas. Considering that water exists in syngas, it is necessary to evaluate the effect of moisture on
chemical stability and hydrogen permeability of the cermet. In this paper, hydrogen permeation rates of
Ni- BaCe0.9Y0.1O3-δ (40:60 in volume ratio) in different water partial pressures were measured at
intermediate temperatures (600-750°C). It is found that hydrogen permeation rate of the cermet is highest
at an appropriate water partial pressure. Samples after experiment were analyzed by XRD, ICP and pH
value measurement, in which Ba(OH)2 and doped CeO2 were found. The reaction of water with samples
resulting in insulating Ba(OH)2 and doped CeO2 is contributed to the decrease of hydrogen permeation in
excessive water partial pressure.
Abstract: SrFe0.6Cu0.3Ti0.1O3-δ (SFCTO) composite-oxide powder was synthesized by citric acid complex
method and studied as mixed oxygen-ionic and electronic conducting membrane material. The formation
process of the perovskite-type compound was detected by XRD, infra-red spectrum and thermo gravimetric
analysis; the effects of ethylene glycol added in the sol formation process on the size distribution of
the powder and the oxygen permeation flux of the membrane were examined. A stable sol was formed
when the molar ratio of total metal ions to citric acid and ethylene glycol was 1:2:3 and the pH value was
5.5; the characteristic absorption peaks of citric acid in the dried gel, O-H and -COO-, moved toward low
frequency direction for 200 cm-1 and 135 cm-1 respectively due to the complexing action of the metal ions
and citric acid. As the dried gel was heated in air up to 400°C, SrCO3 phase appeared by the combustion
of citric acid and ethylene glycol. The perovskite phase started to form at 700 °C, SrCO3 phase reduced
gradually and the single phase of SFCTO was obtained at 900 °C. The SFCTO dense membrane prepared
under the optimum conditions exhibited an oxygen permeation flux of 0.7 ml·min-1·cm-2 at 900°C.
Abstract: A thick film type of limiting current oxygen sensor which uses yttria (8% mol) stabilized
zirconia (YSZ) as oxygen ion conducting solid electrolytes and dense La0.8Sr0.2MnO3 (LSM) as diffusion
barrier was developed successfully. The oxygen sensor showed excellent performance at oxygen
concentrations ranging from 0 to 10 ppm. The advantages of the sensor are simple construction, low cost
and potential long term stability.
Abstract: Mg ion conductors, MgAl2O4 and MgZr4(PO4)6, were prepared by solid state reaction. Their
electrical properties were measured and their application in electrochemical sensors for on-line
determination of Mg in molten Al in the refining process and alloying process was examined. The
activation energies for Mg ion conduction in MgAl2O4 and MgZr4(PO4)6 are 2.08 eV and 1.7 eV,
respectively. The sensors have been found to respond rapidly to the change of Mg content in molten
aluminium around 1000 K.
Abstract: GdSrCoO3-δ and Gd1-XSrXCoO3-δ (x=0.1~0.5) were synthesized using glycine-nitrate process
(GNP). The formation process of perovskite phase and microstructure of powders were characterized
using TG-DTA and XRD. All the powders with different doping amounts of Sr2+ on A-site were
single-phase solid solutions, and the stable perovskite phase was formed completely after calcination at
1100°C. The crystal structures of the solid solutions transfer to a higher symmetrical perovskite.
Abstract: The monoclinic LiMn0.9Cr0.1O2 irreversibly transforms to spinel-like structure m-LiMnO2
during the electrochemical cycling. Experimental results indicated that the (440) interplanar distance of
LixMn2O4 at the charged state increases as the cycle number increases, while the (440) interplanar
distance of LixMn2O4 at the discharged state decreases as the cycle number increases.A model for the
transformation of monoclinic LiMn0.9Cr0.1O2 to the spinel LiMn2O4 is suggested. According to the
suggested model, there may exist two types of s-LixMn2O4 when m-LiMnO2 transforms into s-LixMn2O4.
The two types of spinel LixMn2O4 develop the nanodomain.
Abstract: A series of Mn-doped LiNi0.85−xCo0.15MnxO2 compounds (x= 0, 0.1, 0.2 and 0.4) were prepared
by the co-precipitation method. The effect and mechanism of Mn–doping on the microstructures and
crystallite sizes of LiNi0.85−xCo0.15MnxO2 cathode materials were studied. The non-equivalent substitution
of Mn ions for Ni ions induces a decrease in the average valence of nickel ions. The Mn-doping promotes
the formation of the single phase compounds with more ordered structure.
Abstract: This paper studied structures of ceria-carbonate two-phase composites, with an emphasis on
the interfacial structures and interactions between the two constituent phases of ceria and carbonate. The
phase structure was analyzed by DSC, XRD and SEM. The IR measurements were carried out to identify
the bonding situations and interfaces. Some new absorptions and wavenumber shifts of the bands
appeared in IR spectra. There are strong indications of the interfacial phenomena exist in the two-phase
composites through comparison between the two-phase composite with each individual constituent
phases. The results opened a new interesting subject on the two-phase composite structures with
significant importance for applications in advanced low temperature (300-600°C) SOFC.