Thermal expansion of the W5Si3 and T2 phases of the W–Si–B system investigated by high-temperature X-ray diffraction

The coefficients of thermal expansion (CTE) of the W₅Si₃ and T₂ phases of the W–Si–B system were determined using high-temperature X-ray diffraction in the 298–1273 K temperature interval. Alloys with nominal compositions 62.5W37.5Si (at%) and 58W21Si21B (at%) were prepared from high-purity materials through arc melting followed by heat treatment at 2073 K for 12 h under argon atmosphere. The highly different thermal expansion coefficients of W₅Si₃ along the a (5.0 × 10⁻⁶ K⁻¹) and c (16.3 × 10⁻⁶ K⁻¹) axes lead to a high thermal expansion anisotropy (α_c/α_a ≅ 3.3). On the other hand, the T₂-phase exhibits similar thermal expansion coefficients along the a (6.9 × 10⁻⁶ K⁻¹) and c (7.6 × 10⁻⁶ K⁻¹) axes, indicating a behavior close to isotropic (α_c/α_a ≅ 1.1).     

Z-scan measurements of third-order optical non-linearities in poly(phenylacetylenes)

Poly(phenylacetylene) (PPA) and poly(p-methoxyphenylacetylene) (PMOPPA) were synthesized by catalytic polymerization of monosubstituted alkynes and were fully characterized by conventional techniques. Linear and third-order non-linear optical properties of polymers solutions were investigated at λ=780 nm using a Z-scan set-up equipped with a femtosecond laser source at different operating regimes. A high repetition rate (76 MHz) regime was used to measure the linear and non-linear absorption coefficients by means of thermo-optical effects. Values of the linear and non-linear absorption coefficients were α=4.9×10⁻³ cm⁻¹ and β=1.1×10⁻¹¹ cm W⁻¹ for PPA and α=2×10⁻² cm⁻¹ and β=2.1×10⁻¹⁰ cm W⁻¹ for PMOPPA. Very low repetition rate (14 Hz) excitation was used to evidence the purely-optical non-linear refractive indexes, that were γ=6×10⁻¹⁸ cm² W⁻¹ and γ=11×10⁻¹⁸ cm² W⁻¹, respectively, for PPA and PMOPPA.     

Studies on electrochemical copolymerization of aniline with o-phenylenediamine and degradation of the resultant copolymers via electrochemical quartz crystal microbalance and scanning electrochemical microscope

Electropolymerization of aniline in sulfuric acid solution in the presence of o-phenylenediamine (oPD) of various concentrations was investigated via the electrochemical quartz crystal microbalance (EQCM) technique. It was found that the polymerization occurred more favorably at high aniline-to-oPD molar ratios (F₁, 20 or above). The stabilities of the resultant copolymers against degradation were efficiently improved compared with that of polyaniline (PANI). The first-order kinetic constants for polymer degradation were estimated to be 2.07 × 10⁻³ s⁻¹ for polyaniline, and 3.91 × 10⁻⁴ and 1.28 × 10⁻⁴ s⁻¹ for copolymers with F₁ values of 50 and 20, respectively. The degradation product, benzoquinone, was also detected at the tip electrode of a scanning electrochemical microscope (SECM).     

Ions transport and self-doping in layer-by-layer conducting polymer films

The self-doping mechanism for charge transport is investigated in layer-by-layer (LBL) films from two conducting polymers, namely poly(o-methoxyaniline) (POMA) and poly(3-thiophene acetic acid) (PTAA). The efficiency of charge intercalation, defined as the ratio between the charge and the mass change, is twice for the POMA/PTAA LBL film in comparison with a cast POMA film. This is attributed to differences in the diffusion-controlled charge and mass transport, where distinct ionic species participate in the LBL films, as demonstrated with experiments using a quartz crystal microbalance. The doping efficiency for LBL film is the same, i.e., 3.93 × 10⁻⁴ and 3.56 × 10⁻⁴ g/C for the Li⁺ and (C₂H₅)₄N⁺ doped films, and is different for the cast POMA film, i.e., 11.3 × 10⁻⁴ for Li⁺ and 6.45 × 10⁻⁴ g/C for (C₂H₅)₄N⁺. Therefore, once no significant differences in the intercalation mechanism are observed when different cations, Li⁺ or (C₂H₅)₄N⁺, are used with the LBL films, this indicates that the self-doping mechanism is controlled by the exchange of anions.     

Synthesis,characterization and evaluation of cation-ordered LnBaCo2O5+δ as materials of oxygen permeation membranes and cathodes of SOFCs

LnBaCo₂O_5+δ (Ln = La, Pr, Nd, Sm, Gd, and Y) was synthesized via an EDTA–citrate complexing process. The particular Ln³⁺ dopant had a significant effect on the oxide’s phase structure/stability, oxygen content, electrical conductivity, oxygen permeability, and cathode performance. Stable, cation-ordered oxides with layered lattice structures were obtained with medium-sized Ln³⁺ ions over a wide range of oxygen partial pressures, a property essential for applications as oxygen separation membranes and solid oxide fuel cell (SOFC) cathodes. PrBaCo₂O_5+δ demonstrated the highest oxygen flux (∼5.09 × 10⁻⁷ mol cm⁻² s⁻¹ at 900 °C), but this value was still significantly lower than that of Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ perovskite (∼3.1 × 10⁻⁶ mol cm⁻² s⁻¹ at 900 °C). The observed difference was attributed to the much longer diffusion distance through a polycrystalline membrane with a layered lattice structure than through cubic perovskite because bulk diffusion was the rate-limiting step of permeation. An area-specific resistance of ∼0.213 Ω cm² was achieved at 600 °C with a PrBaCo₂O_5+δ cathode, suggesting that the layer-structured oxides were promising alternatives to ceramic membranes for SOFC cathodes.     

Laser doping of chromium as a double acceptor in silicon carbide with reduced crystalline damage and nearly all dopants in activated state

Chromium, a p-type dopant, has been incorporated into silicon carbide by laser doping. Secondary ion mass spectrometric data revealed enhanced solid solubility (2.29 × 10¹⁹ cm⁻³ in 6H–SiC and 1.42 × 19¹⁹ cm⁻³ in 4H–SiC), exceeding the equilibrium limit (3 × 10¹⁷ cm⁻³ in 6H–SiC above 2500 °C). The roughness, surface chemistry and crystalline integrity of the doped sample were examined by optical interferometry, energy dispersive X-ray spectrometry and transmission electron microscopy, respectively, and showed no crystalline disorder due to laser heating. Deep-level transient spectroscopy confirmed Cr as a deep-level acceptor with activation energies E_v + 0.80 eV in 4H–SiC and E_v + 0.45 eV in 6H–SiC. The Hall effect measurements showed that the hole concentration (1.942 × 10¹⁹ cm⁻³) is almost twice the average Cr concentration (1 × 10¹⁹ cm⁻³), confirming that almost all of the Cr atoms were completely activated to the double acceptor state by the laser-doping process without requiring any additional annealing step.     

Analysis of electrochemical impedance of polypyrrole|sulfate and polypyrrole|perchlorate films

PPy|SO₄ and PPy|ClO₄ films have been synthesized and investigated in K₂SO₄, ZnSO₄ and NaClO₄ aqueous solutions by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and electron probe microanalysis (EPMA) methods. On the basis of obtained data and calculated impedance parameters as the potential functions, the role of different processes (diffusion of ions, double-layer charging, adsorption and charge transfer) in oxidized, partially reduced and reduced PPy films is estimated. The lowest pseudocapacitance values (from n × 10⁻⁶ to n × 10⁻⁴ μF cm⁻² for 1 μm film), independent of solution concentration, were established for PPy|SO₄ in ZnSO₄. This phenomenon is related with strongly aggravated film reduction process in the solution of double-charged cations. In the case of PPy|ClO₄ in NaClO₄ and PPy|SO₄ in K₂SO₄,where the mono-charged cations participate in redox process, the capacitance values are in the range from: n × 10⁻³ to n × 10⁻² μF cm⁻² and even somewhat higher for PPy|ClO₄ system at oxidized state. The calculated effective diffusion coefficients of ions D remain inside the range from n × 10⁻¹² to n × 10⁻¹⁴ cm² s⁻¹ for PPy|SO₄ in 0.1 M K₂SO₄ and PPy|ClO₄ in 0.1 M NaClO₄ aqueous solution. In the case of PPy|SO₄ film in ZnSO₄ solution the D values are essentially lower.     

The effect of a novel organic compound chiral macrocyclic tetraamide-I interfacial layer on the calculation of electrical characteristics of an Al/tetraamide-I/p-Si contact

The Al/tetraamide-I/p-Si Schottky barrier diode (SBD) has been prepared by adding a solution of a novel nonpolymeric organic compound chiral macrocylic tetraamide-I in chloroform on top of a p-Si substrate and then evaporating the solvent. It has been seen that the forward-bias current–voltage (I–V) characteristics of Al/tetraamide-I/p-Si SBD with a barrier height value of 0.75 eV and an ideality factor value of 1.77 showed rectifying behaviour. The energy distribution of the interface state density determined from I–V characteristics increases exponentially with bias from 5.81 × 10¹² cm⁻² eV⁻¹ at (0.59-E_v) eV to 1.02 × 10¹³ cm⁻² eV⁻¹ at (0.40-E_v) eV. It has showed that space charge limited current (SCLC) and trap charge limited current (TCLC) are the dominant transport mechanisms at large forward-bias voltages.     

Alkyl chain length dependence of the field-effect carrier mobility in regioregular poly(3-alkylthiophene)s

The field-effect mobility of holes in regioregular poly(3-alkylthiophene)s was determined for a series of 5 alkyl chain lengths from C₄ (n-butyl) to C₁₂ (n-dodecyl). Contrary to a previous report, a non-monotonic dependence of field-effect mobility on alkyl chain length was found. The average hole mobility varied from 1.2 × 10⁻³ cm²/Vs in poly(3-butylthiophene) and 1 × 10⁻² cm²/Vs in poly(3-hexylthiophene) to 2.4 × 10⁻⁵ cm²/Vs for poly(3-dodecylthiophene). We believe that the hexyl side chain is optimum for charge transport because of better self-organization in poly(3-hexylthiophene) compared to other polymers in the series. The present results provide an important structure–carrier mobility relationship for the regioregular poly(3-alkylthiophene)s which are of wide interest for thin film transistors and photovoltaic cells.     

Theoretical and experimental study of photocurrent action spectrum of ITO/sexithiophene/Al structure

We have studied photovoltaic cells using sexithiophene in (ITO/6T/Al) structure, and we have measured the action spectrum obtained by illumination through the aluminum side which is compared to the measured absorption spectrum. Two models were used to interpret this experiment: the Ghosh model using the carriers diffusion property in the bulk, and the kinetic model describing the dynamic behavior of the charge carriers in the device. The confrontation of these models with the experimental spectra allows us to reach the diffusion length of electron–hole pair L=2×10⁻⁶ cm. We also give the mobility of carriers (μ_n≈1.5×10⁻⁴ cm²/V s, and μ_p≈1.5×10⁻⁵ cm²/V s) and their diffusion coefficients (D_n≈4×10⁻⁶ cm²/s, and D_p≈4×10⁻⁷ cm²/s).     

Kinetic study of the electrochemical degradation of polyaniline

The kinetics of the electrochemical degradation of polyaniline (PANI) layers, deposited by electropolymerization and chemical polymerization onto platinum electrode, was investigated in an acid aqueous solution. The degradation rate was shown to depend greatly on the electrode potential applied. First-order rate constants of degradation, obtained from the kinetic data, were shown to vary between 2.87×10⁻⁵ and 3.11×10⁻³ s⁻¹ for thick PANI films, having the electrochemical charge density of 14 mC/cm², and between 2.0×10⁻⁵ and 3.60×10⁻³ s⁻¹ for thin PANI films, having the charge density of 1.5 mC/cm², within the electrode potential range of 0.3–0.9 V versus Ag/AgCl. Two linear regions were found to present on the dependencies of logarithm of the first-order degradation rate constant on electrode potential, one of them having a slope of 0.44 and 1.34 V⁻¹ within electrode potential limits of 0.3–0.6 V, and another one having a slope of 6.37 and 6.39 V⁻¹ within potential limits of 0.6–0.9 V, for thick and thin polymer films, respectively. The results obtained show that the electrochemical degradation of PANI films proceed at a remarkable rate even at low electrode potential values.     

Protonation-induced rearrangements in Langmuir films and redox properties of Langmuir–Blodgett films of 2-(n-alkyl)fulleropyrrolidines

The effect of protonation of the pyrrolidine ring nitrogen of 2-(n-alkyl)fulleropyrrolidines, C₆₀pyr–C_m (m=4, 6, 8, 10 and 12), on the properties of the Langmuir and Langmuir–Blodgett (LB) films was investigated. The isotherms of both surface pressure (π) and surface potential change (ΔV) versus area per molecule (A) for the Langmuir films of C₆₀pyr–C_m were determined simultaneously. It was found that the longer the alkyl chain of the fulleropyrrolidine the larger is the film compressibility, κ, i.e., κ(C₆₀pyr–C₄)=(2.1±0.4)×10⁻² m mN⁻¹, κ(C₆₀pyr–C₈)=(3.5±0.4)×10⁻² m mN⁻¹ and κ(C₆₀pyr–C₁₂)=(4.1±0.5)×10⁻² m mN⁻¹, as expected for the liquid surface films. The values of surface area at zero surface pressure (A₁) differ in the range 0.6 nm² molecule⁻¹ (for m=4–8) to 1.4 nm² molecule⁻¹ (for m=10–12), indicating that all 2-(n-alkyl)fulleropyrrolidines form multilayer or aggregated films on neutral water subphase. However, acidification of the water subphase increases the A₁ values for all investigated fulleropyrrolidines up to ca. 1.9 nm² molecule⁻¹, i.e., the value corresponding to maximum area occupied by a fulleropyrrolidine at horizontal orientation in a monolayer film. Apparently, 2-(n-alkyl)fulleropyrrolidinium cations formed at low pH are markedly de-aggregated in the films and their orientation is changed due to protonation of the pyrrolidine nitrogen. Similarly, however, less pronounced effects are observed if ionic strength of the subphase solution, I, is increased in the range 0≤I≤1.0 mol dm⁻³ NaCl. The Langmuir films formed on a water subphase were the most stable with respect to the LB transfer onto 5 MHz Au–quartz crystal vibrators. Simultaneous cyclic voltammetry and piezoelectric microgravimetry at an electrochemical quartz crystal microbalance of these films showed at least two electroreductions where the fulleropyrrolidine mono anions were stable with respect to dissolution.     

Deformation behavior of Zr55.9Cu18.6Ta8Al7.5Ni10 bulk metallic glass matrix composite in the supercooled liquid region

A Zr_55.9Cu_18.6Ta₈Al_7.5Ni₁₀ bulk metallic glass (BMG) composite with an amorphous matrix reinforced by micro-scale particles of Ta-rich solid solution was prepared by copper-mold casting. Isothermal compression tests of the BMG composite were carried out in the range from glass transition temperature (∼673 K) to onset crystallization temperature (∼769 K) determined by differential scanning calorimetry (DSC). The compressive deformation behavior of the BMG composite in the supercooled region was investigated at strain rates ranging from 1 × 10⁻³ s⁻¹ to 8 × 10⁻² s⁻¹. It was found that both the strain rate and test temperature significantly affect the stress–strain behavior of the BMG composite in the supercooled liquid region. The alloy exhibited Newtonian behavior at low strain rates but became non-Newtonian at high strain rates. The largest compressive strain of 0.8 was achieved at a strain rate of 1 × 10⁻³ s⁻¹ at 713 K. The strain rate change method was employed to obtain the strain rate sensitivity (m). The deformation mechanism was discussed in terms of the transition state theory based on the free volume.     

Controlling of silicon–insulator–metal junction by organic semiconductor polymer thin film

Electrical and photovoltaic properties of a metal–semiconductor–insulator–polymer–metal diode were investigated. The n-Si/SiO₂/MEH-PPV/Al diode shows a rectifying behavior with the rectification ratio of 2.22 × 10⁵ at ±5 V and exhibits a non-ideal behavior due to the series resistance and oxide-organic layers. The organic semiconductor makes a contribution to the I–V characteristics of the diode and the trap-charge limited space charge and space charge limited current mechanisms were observed for the diode. The current–voltage characteristics of the n-Si/SiO₂/MEH-PPV/Al diode under different illumination intensities give an open circuit voltage (V_oc) along with a short circuit current (I_sc). This suggests that the n-Si/SiO₂/MEH-PPV/Al diode is a photovoltaic device with V_oc = 0.456 V and J_sc = 7.89 × 10^?8 A/cm² values under 100 mW/cm² illumination intensity. The photoconductivity mechanism of the diode is controlled by monomolecular recombination. The interface state density D_it values with time constant τ_it of the diode under dark and illumination conditions were found to be 2.53 × 10¹⁰ eV^?1 cm^?2 with 5.09 × 10^?5 s and 2.50 × 10¹⁰ eV^?1 cm^?2 with 8.27 × 10^?5 s, respectively. The obtained results indicate that the n-Si/SiO₂/MEH-PPV/Al diode is a photo-sensitive diode.     

The calculation of electronic properties of an Ag/chitosan/n-Si Schottky barrier diode

In this study, the film of chitosan by adding the solution of chitosan being a polymeric compound on the top of an n-Si substrate and then by evaporating solvent was formed. It was seen that the chitosan/n-Si contact demonstrated clearly rectifying behavior and the reverse curves exhibit a weak bias voltage dependence by the current–voltage (I–V) curves studied at room temperature. Average barrier height and ideality factor values for this structure were determined as 0.94 eV and 1.81, respectively. Furthermore, the energy distribution of the interface state density located in the semiconductor band gap at the chitosan/n-Si substrate in the energy range (E_c−0.785) to (E_c−0.522) eV have been determined from the I–V characteristics. The interface state density N_ss ranges from 5.39 × 10¹² cm⁻² eV⁻¹ in (E_c−0.785) eV to 1.52 × 10¹³ cm⁻² eV⁻¹ in (E_c−0.522) eV. The interface state density has an exponential rise with bias from the midgap towards the bottom of the conduction band.     

Effect of growth rate on microstructure and mechanical properties of directionally solidified multiphase intermetallic Ni–Al–Cr–Ta–Mo–Zr alloy

The effect of growth rate on microstructure and mechanical properties of directionally solidified (DS) multiphase intermetallic alloy with the chemical composition Ni–21.9Al–8.1Cr–4.2Ta–0.9Mo–0.3Zr (at.%) was studied. The DS ingots were prepared at constant growth rates V ranging from 5.56 × 10⁻⁶ to 1.18 × 10⁻⁴ ms⁻¹ and at a constant temperature gradient at the solid–liquid interface of G_L = 12 × 10³ K m⁻¹. Increasing growth rate increases volume fraction of dendrites and decreases primary dendritic arm spacing, mean diameter of α-Cr (Cr-based solid solution) and γ′(Ni₃Al) precipitates within the dendrites. Room-temperature compressive yield strength, ultimate compressive strength, hardness and microhardness of dendrites increase with increasing growth rate. All room-temperature tensile specimens show brittle fracture without yielding. The brittle-to-ductile transition temperature for tensile specimens is determined to be about 1148 K. Minimum creep rate is found to depend strongly on the applied stress and temperature according to the power law with a stress exponent of n = 7 and apparent activation energy for creep of Q_a = 401 kJ/mol.     

Structure and properties of solid-state synthesized poly(3′,4′-ethylenedioxy-2,2′:5′,2″-terthiophene)

A polyterthiophene derivative: poly(3′,4′-ethylenedioxy-2,2′:5′,2″-terthiophene) was synthesized by solid-state oxidative-polymerization of 3′,4′-ethylenedioxy-2,2′:5′,2″-terthiophene (TET) in various ratios of oxidant (FeCl₃) to the monomer (TET). The resulting polymers were characterized by FT-IR, ¹H NMR, TEM, SEM, UV–vis–NIR, GPC, X-ray diffraction, EDX, CV, galvanostatic charge–discharge, as well as TGA and conductivity measurements. The results showed that the as-made poly(TET)s were partially in doped state with a conductivity ranging from 2.1 × 10^?3 S cm^?1 to 8.1 × 10^?3 S cm^?1 at room temperature, and exhibited good thermal stability in nitrogen up to 337–356 °C. The poly(TET)s showed a similar UV–vis absorption peak at 462 nm in acetonitrile. In addition, as-made poly(TET)s had low molecular weight ranging from 3300 to 3500 with microstructured morphology including nanorodes and nanofibers, and presented one redox couple at 1.1–1.2 V(ox) and 0.6–0.7 V(re) in 0.1 M Et₄NBF₄ acetonitrile solution. A moderate specific capacitance of 71 F g^?1 for poly(TET) modified graft electrode was obtained within the potential range of ?0.2 V to 0.5 V in 1 M H₂SO₄ solution. X-ray diffraction results imply the enhanced crystallinity of poly(TET)s, indicating the existence of crystalline phase in polymer matrix. Furthermore, the comparison of results from every measurement indicated that the [FeCl₃]/[TET] ratio strongly affects the morphology of the poly(TET), and the fibrillar growth tendency of poly(TET) was observed with the increase of the [FeCl₃]/[TET] ratio, and long-length fibrillar morphology occurred in the highest [FeCl₃]/[TET] ratio.     

Crystal and molecular structure of the new anion-radical salts—(N-Me-2-NH2-Pz)(TCNQ)2 and (N-Me-Tetra-Me-Pz)(TCNQ)2 (Pz is pyrazine)

Two anion-radical salts (ARS) of 7,7′,8,8′-tetracyanoquinodimethane (TCNQ) – (N-Me-2-NH₂-Pz)(TCNQ)₂ and (N-Me-Tetra-Me-Pz)(TCNQ)₂ (N-Me-2-NH₂-Pz, N-methyl-2-amino-pyrazinium-; N-Me-Tetra-Me-Pz, N-methyl-tetra-methyl-pyrazinium-ions) – were synthesized and characterized. Both salts (ARS) were found to be semiconductors with a room-temperature conductivity of 3.8 × 10⁻⁵ and 1.93 × 10⁻² Ω⁻¹ cm⁻¹, respectively. For both salts a layered structure of cations and anion-radicals was discovered, where layers composed of cations alternate along the b-axis with the layers containing TCNQ anion-radicals. The cations in the (N-Me-2-NH₂-Pz)(TCNQ)₂ form pairs bonded by strongly shortened 1.97 (2) Å intermolecular hydrogen N(1)…H(3a) links.     

Synthesis and nonlinear optical properties of novel polyurethanes with high thermal stability of dipole alignment

2,3-Di-(2′-hydroxyethoxy)-4′-nitrostilbene (2) was prepared and condensed with 2,4-toluenediisocyanate (TDI), 3,3′-dimethoxy-4,4′-biphenylenediisocyanate and 1,6-hexamethylenediisocyanate to yield polyurethanes (3–5) containing the nonlinear optical (NLO)-chromophores 2,3-dioxynitrostilbenyl groups, which constitute parts of the polymer backbones. The resulting polymers (3–5) were soluble in common organic solvents such as acetone and N,N-dimethylformamide (DMF). These polymers showed a thermal stability up to 260 °C in thermogravimetric analysis (TGA) thermograms with glass transition temperature (T_g) values in the range 100–155 °C in differential scanning calorimetry (DSC) thermograms. The second harmonic generation (SHG) coefficients (d₃₃) of poled polymer films were around 5.48×10⁻¹⁰ esu. These poled polymers exhibited a greater thermal stability of dipole alignment even at 20 °C higher than T_g due to the partial main chain character of the polymer structure, which is acceptable for NLO device applications.     

Electrical properties,sintering and thermal expansion behavior of composite ceramic interconnecting materials,La0.7Ca0.3CrO3−δ/Y0.2Ce0.8O1.9 for SOFCs

This paper presents a high-performance interconnect ceramic for solid oxide fuel cells (SOFCs), based on a modification of La_0.7Ca_0.3CrO_3−δ (LCC). It was found that addition of a small amount of YDC (Y_0.2Ce_0.8O_1.9) into LCC dramatically increased the electrical conductivity. For the best system, LCC + 3 wt.% YDC, the electrical conductivity reached 104.8 S cm⁻¹ at 800 °C in air. The electrical conductivity of the specimen with 2 wt.% YDC in H₂ at 800 °C was 5.9 S cm⁻¹. With the increase of YDC content, the relative density increased, reaching 97.6% when the YDC content was 10 wt.%. The average coefficient of thermal expansion (CTE) at 30–1000 °C in air increased with YDC content, ranging from 11.12 × 10⁻⁶ K⁻¹ to 15.34 × 10⁻⁶ K⁻¹. The oxygen permeation measurement illustrated a negligible oxygen ionic conduction, indicating that it is still an electronically conducting ceramic. Therefore, it is a very promising interconnecting ceramic for SOFCs.