Glycine-nitrate Method Research Articles

Exchange Bias Effect in La1-xAgxMnO3Nanopowders

Exchange bias (EB) phenomena were first observed in the La1-xAgxMnO3 as prepared and heat treated (300 o C/2 hours) nanopowders (x = 0.10, 0.15 and 0.20) which were synthetized by self-combustion glycine-nitrate method. These nanoparticles have an average size of about 25 nm and adopt orthorhombic Pnma crystal structure. Cooling in magnetic field Hcf M 0 through the Curie temperature TC shifts hysteresis loop in horizontal and vertical direction. The values of exchange bias field HE, coercive field Hc, remnant asymmetry ! E and coercive magnetization ! c increase with increasing value of cooling field Hcf. In addition the training effect was observed. Basic magnetic properties like the Curie temperature TC and the saturated magnetization µs increase and HE or ! E decrease with heat treatment. Heat treatment at 600 o C/2 hours increases the average size of nanoparticles to about 55 nm, crystal structure changes to rhombohedral structure (space group ! ! ) and EB effect vanishes.

Enhanced performance of nanocrystalline Cu-doped Pr0.6Sr0.4FeO3 as cathode for solid oxide fuel cell

Pr0.6Sr0.4FeO3 (PSF) and Pr0.6Sr0.4Fe0.8Cu0.2O3 (PSFCu) perovskite materials were prepared by glycine nitrate method as a cathode material for intermediate temperature solid oxide fuel cells (IT-SOFC). The prepared PSF and PSFCu materials exhibited typical orthorhombic structure and highly porous morphology with high surface area (43–55m2/g). Upon the 20% Cu doping on the B-site of the PSF, the electrical conductivity increased from 247Scm−1 (PSF cathode) to 298Scm−1 and polarization resistance of symmetry cell decreased from 0.21Ωcm2 (PSF cathode) to 0.14Ωcm2 as compared to PSF cathode (0.21Ωcm2) at 850°C. Cu doping in B-site of the perovskite generates the oxide ion vacancies which lead the high effective charge carriers, resulting in the enhanced electrochemical performance of PSFCu cathode.

Anomalous Magnetic Behavior of Sm0.8Ca0.2MnO3 Nanoparticles

Magnetic properties of compacted Sm0.8Ca0.2MnO3 (SCMO) particles with average particle size of 23-100 nm, prepared by the glycine-nitrate method, have been investigated. It was found that the relative volume of the ferromagnetic phase decreases with decreasing particle size. Curves of field cooled and zero filed cooled magnetization (M(ZFC)) exhibit a bifurcation just below the Curie temperature (T(c) approximately 55-64 K) for all particles studied. The field dependence of M(ZFC) peak follows de Almeida-Thouless line. Both features are characteristic of spin-glasses (SG). Measurements of ac-susceptibility in the temperature range 5-300 K and the frequency range f = 10 Hz-10 kHz show a sharp peak for both real and imaginary components in the vicinity of T(c), apparently attributed to the Hopkinson effect. A second small peak is seemingly associated with antiferromagnetic or ferrimagnetic ordering. Though, for smaller particles both peaks depend on frequency, no shift to higher temperatures with increasing f, characteristic for SG systems, was observed. The dissimilarity in magnetic properties and dynamic characteristics observed for SCMO and for La0.8Ca0.2MnO3 nanoparticles is discussed, taking into account a difference in the width of the band and the strength of double exchange and interparticle interactions.

Nanometer Size Effect on Structural and Magnetic Properties of La0.2Ca0.8MnO3

Structural and magnetic properties of La0.2Ca0.8MnO3 nanoparticles with average size of 15-37 nm, prepared by the glycine-nitrate method, have been studied. Synchrotron experiments performed in the temperature range of 80-300 K have shown that a structural transition from room temperature orthorhombic Pnma to monoclinic P2(1)/m space group, associated with orbital ordering, occurs below 200 K in the studied particles. This transition observed for the largest particles of 37 nm is very close to that of bulk, as seen by similar temperature variation of lattice parameters and orthorhombic strain. The transition is highly suppressed for smaller 15 nm particles. Horizontal and vertical shifts of magnetic hysteresis loops (M(Shift) and H(EB)), displayed in a field cooled process, indicate size dependent exchange bias effect. It is also shown that M(shift) and H(EB), as well as the remanent magnetization M(r) and coercive field H(c) at low temperatures, exhibit a non-monotonic size dependence for particles around 23 nm. These effects may be attributed to the changes in uncompensated spins at the surface, anisotropy or alternatively to a transition from a multi-domain to the single domain state.

Magnetic properties of electron-doped La0.23Ca0.77MnO3 nanoparticles

Magnetic properties of electron-doped La0.23Ca0.77MnO3 manganite nanoparticles, with average size of 12 and 60 nm, prepared by the glycine–nitrate method, have been investigated in the temperature range 5–300 K and magnetic fields up to 90 kOe. It is suggested that weak ferromagnetic moment results from ferromagnetic shells of the basically antiferromagnetic nanoparticles and from domains of frustrated disordered phase in the core. Assumption of two distinct sources of ferromagnetism is supported by the appearance of two independent ferromagnetic contributions in the fit of the T 3/2 Bloch law to spontaneous magnetization. The ferromagnetic components, which are more pronounced in smaller particles, occupy only a small fraction of the nanoparticle volume and the antiferromagnetic ground state remains stable. It is found that the magnetic hysteresis loops following field cooled processes, display size-dependent horizontal and vertical shifts, namely, exhibiting exchange bias effect. Time-dependent magnetization dynamics demonstrating two relaxation rates were observed at constant magnetic fields upon cooling to T < 100 K.

Chemical compatibility, redox behavior, and electrochemical performance of Nd1−xSrxCoO3−δ cathodes based on Ce1.9Gd0.1O1.95 for intermediate-temperature solid oxide fuel cells

The effect of Sr substitution for Nd on Nd1−xSrxCoO3−δ (NSC) (x=0.3, 0.4, 0.5, 0.6, and 0.7) is investigated to evaluate NSC as a cathode material based on Gd0.1Ce0.9O1.95 (GDC) electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The NSC powders are prepared by the glycine nitrate method. At a given temperature, the electrical conductivity increases with increasing Sr content up to x=0.5 and then decreases for x>0.5. The redox behavior of NSC (x=0.3, 0.5, and 0.7) cathodes is studied by the coulometric titration at 700°C. In order to investigate the area specific resistances of NSC–GDC cathodes, symmetrical half cells (cathode/electrolyte/cathode) are measured using impedance spectroscopy at various temperatures in air under open circuit voltage (OCV) condition. The electrochemical performance of NSC–GDC cathodes is measured using an NSC–GDC/GDC/Ni-GDC anode supported cell. The maximum power density of NSC–GDC cathodes increases with increasing strontium content up to x=0.5 and then decreases at 700°C. In terms of electrical conductivity and electrochemical performance, Nd1−xSrxCoO3−δ (x=0.5) is more suitable as a cathode material based on GDC electrolyte in IT-SOFC applications.

Nanometer Size Effect on Magnetic Properties of Sm0.8Ca0.2MnO3 Nanoparticles

Magnetic properties of compacted Sm0.8Ca0.2MnO3 (SCMO) particles with average particle size of 23–100 nm, prepared by the glycine-nitrate method, have been investigated. It was found that the relative volume of the ferromagnetic phase decreases with decreasing particle size. Curves of field-cooled and zero-field-cooled magnetization (MZFC) exhibit a bifurcation just below the Curie temperature, TCdc ≈ 55–64 K, determined from magnetization measurements for all particles studied. The field dependence of MZFC peak shows reasonable agreement with both the de Almeida–Thouless H2/3 line and the H2 power law. Measurements of ac susceptibility in the temperature range 5–300 K and the frequency range f = 10 Hz to 10 kHz show a sharp peak for both real and imaginary components in the vicinity of TCdc, apparently attributed to the Hopkinson effect. The Curie temperature determined by zeroing the imaginary part of ac susceptibility χ″(T) shows a larger value of TC ≈ 85–90 K in compliance with TC of bulk Sm0.8Ca0.2MnO3 sample. A second small peak in ac susceptibility at T ≈ 11–15 K is seemingly associated with antiferromagnetic or ferrimagnetic ordering. Although for smaller particles both peaks depend on frequency, no shift to higher temperatures with increasing f, characteristic for spin-glass (SG) systems, was observed. Smallest, 23 nm, SCMO particles exhibit “waiting time” dependence in time evolution of MZFC, a feature expected for SG. These particles do not show any memory effects in MZFC, which is in strong contrast with the usual behavior exhibited by ferromagnetic nanoparticles with strong enough interparticle interaction. The dissimilarity in magnetic properties and dynamic characteristics observed for SCMO and for La0.8Ca0.2MnO3 nanoparticles is discussed, taking into account a difference in the width of the band and the strength of double exchange and interparticle interactions.

Strategies for pursuing community involvement in OTIS research studies

Nanocrystalline Mg0.6Cd0.4Fe2O4 ferrite powders were produced by the glycine-nitrate auto-combustion method for the first time. The influence of the different molar ratios of glycine-to-nitrate G.N−1) on the characteristics of the prepared powders was systematically investigated by X-ray diffraction (XRD), inductively coupled plasma optical emission spectroscopy (ICP-OES), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FE-SEM) and vibrating sample magnetometry (VSM). Thermodynamic calculations revealed that the adiabatic flame temperature changes from 598.79 K to 1757.97 K by increasing the G.N−1 ratios from 0.30 to 0.85. The results confirmed that under fuel-lean combustion (G.N−1 = 0.30), Mg0.6Cd0.4Fe2O4 nanoparticles can be obtained at a significantly lower temperature and shorter synthesis time, compared to other preparation methods like standard ceramic and co-precipitation. The XRD and ICP results showed that the crystallite size of the powders changes in the range of 8–43 nm, and their Cd content notably decreases with increasing the G.N−1 values. The FE-SEM results proved that the porosity and size of the as-prepared ferrite nanoparticles drastically change with variations in the G.N−1 ratio. The evolution of phase, crystallite/particle size, and magnetic properties after annealing was discussed in detail. At the optimized annealing condition, the synthesized Mg0.6Cd0.4Fe2O4 ferrite offered a high saturation magnetization of 41.70 Am2 kg−1 and a coercivity of 1.92 kA m−1, indicating noticeably better soft magnetic properties compared to the same ferrite produced by the other wet chemical methods.

Electrocatalytic Behavior of Calcium Doped LaFeO3 as Cathode Material for Solid Oxide Fuel Cell

La(1-x)Ca(x)FeO3 (X = 0.0, 0.2, 0.4, abbreviated as LCF) as cathode material for intermediate temperature solid oxide fuel cells (IT-SOFC) was synthesized by new route of glycine nitrate method. LCF materials were characterized by X-ray diffraction (XRD), scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM), electrical and electrochemical impedance spectroscopy (EIS). The powder LCFs exhibited single phase with orthorhombic structure, highly porous and small nanoparticles with average size of 200-300 nm. The electrical conductivities of LCFs increased as increasing the Ca content and achieved the maximum electrical conductivity of 148 Scm(-1) for La0.6Ca0.4FeO3 (X = 0.4) at 550 degrees C. The improved conductivity of LCFs could be a promising cathode material for IT-SOFCs. In the impedance analysis of fabricated symmetry cell with the optimized La0.6Ca0.4FeO3 cathode and Ce0.8Sm0.2O3 (SDC) electrolyte, the minimum area specific resistance (ASR) of 0.15 omegacm2 was observed at 850 degrees C, which may due to the lowest activation energy (1.55 eV), resulting from the reduction of oxygen molecules into oxygen ions. It was found that calcium doping was essential to increase the charge carrier concentration of lanthanum iron oxide materials, resulting in the high conductivity at intermediate temperature.

Electrochemical Impedance Spectroscopy of Ba2In2O5: Effect of Porosity, Grain Size, Dopant, Atmosphere and Temperature

Electrochemical impedance spectroscopy was used to investigate the electrical properties of Ba2In2O5 and the effect of porosity, dopant (Ce), atmosphere, temperature, and grain size on these properties. The effect of dopant was investigated by comparing the results of undoped Ba2In2O5 samples to Ce-doped Ba2In2O5 samples. Effect of grain size for both compositions was studied by comparing the samples made by the glycine-nitrate method, which resulted in smaller grain sizes, and the samples made by the solid-state process, which resulted in larger grain sizes. Porosity effects were determined by testing the samples with different porosities between 20% and 50%. All samples were tested in two different atmospheres, air and 50% H2/50% N2, and at different temperatures in the range from 100°C to 500°C. The study contributed to better understanding of the conducting mechanisms of Ba2In2O5 in air and hydrogen-containing atmospheres.

A Novel Method to Improve the Electrochemical Performance of LiMn 2O 4 Cathode Active Material by CaCO 3 Surface Coating

Spinel LiMn2O4 was synthesized by glycine-nitrate method and coated with CaCO3 in order to enhance the electrochemical performance at room temperature (25°C) and 55°C. The uncoated and CaCO3-coated LiMn2O4 materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical tests. XRD and SEM results indicated that CaCO3 particles encapsulated the surface of the LiMn2O4 without causing any structural change. The charge-discharge tests showed that the specific discharge capacity fade of pristine electrode at 25 and 55°C were 25.5% and 52%, respectively. However, surface modified cathode shows 7.4% and 29.5% loss compared to initial specific discharge capacity at 70th cycle for 25 and 55°C, respectively. The improvement of electrochemical performance is attributed to suppression of Mn2+ dissolution into electrolyte via CaCO3 layer.

Electrochemical performance of unsintered Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3− δ, La 0.6Sr 0.4Co 0.8Fe 0.2O 3− δ, and La 0.8Sr 0.2MnO 3− δ cathodes for metal-supported solid oxide fuel cells

The electrochemical performances of Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3− δ (BSCF), La 0.6Sr 0.4Co 0.8Fe 0.2O 3− δ (LSCF), and La 0.8Sr 0.2MnO 3− δ (LSM) cathodes fabricated without pre-sintering were studied. The BSCF starting powder prepared by the glycine nitrate method exhibited a single perovskite structure and no secondary phase was detected using XRD. SEM images revealed that the unsintered BSCF particles were highly agglomerated even before exposure to the operating temperature of the solid oxide fuel cell (SOFC). Unlike the LSM and LSCF cathodes, the BSCF cathode could be sintered at the SOFC operating temperature of 1073 K, and therefore exhibited porosity and good connectivity among particles. As determined using electrochemical impedance spectroscopy measurements, the lowest polarization resistances were found to be 0.13 Ω cm 2 for unsintered BSCF, 0.22 Ω cm 2 for unsintered LSCF, and 3.19 Ω cm 2 for unsintered LSM. The single-cell power density curves had maximal power densities of 0.91 W cm −2, 0.77 W cm −2, 0.60 W cm −2 for anode-supported SOFCs using unsintered BSCF, LSCF, and LSM cathodes, respectively. For practical aspect, the power densities of 0.72, 0.6 and 0.5 W cm −2 were obtained at 0.7 V from anode-supported SOFCs with unsintered BSCF, LSCF and LSM cathodes, respectively. The metal-supported cells having unsintered BSCF cathode had maximum power densities at 0.82 W cm −2, and a power density of 0.74 W cm −2 at 0.7 V was observed.

Low-temperature sintering and electrical properties of strontium- and magnesium-doped lanthanum gallate with V2O5 additive

The effects of a V2O5 additive on the low-temperature sintering and ionic conductivity of strontium- and magnesium-doped lanthanum gallate (LSGM: La0.8Sr0.2Ga0.8Mg0.2O2.8) are studied. The LSGM powders prepared by the glycine nitrate method are mixed with 0.5–2at.% of VO5/2 and then sintered at 1100–1400°C in air for 4h. The apparent density and phase purity of the LSGM specimens are increased with increasing sintering temperature and VO5/2 concentration due to the enhanced sintering and mass transfer via the intergranular liquid phase. The 1at.% VO5/2-doped LSGM specimen sintered at 1300°C exhibits a high oxide ion conductivity of ∼0.027Scm−1 at 700°C over a wide range of oxygen partial pressure (PO2=10−27−1 atm), thereby demonstrating its potential as a useful electrolyte for anode-supported solid oxide fuel cells (SOFCs) without the requirement for any buffer layer between the electrolyte and anode.

The persistence of the magnetocaloric effect in (La1−xAx)0.67Ba0.33Mn1.05O3−δ

Polycrystalline samples of (La1−xAx)0.67Ba0.33Mn1.05O3−δ, with A being a mixture of lanthanides containing 66% La, 22% Nd, 8% Pr, and 4% Ce, were prepared by the glycine-nitrate method, with target compositions of x=0, 0.33, 0.67, and 1. The effect of the mixture of lanthanides on the Curie temperature, TC, and the magnetocaloric properties was investigated. The prepared samples are single phase, with space group R3¯c. The lattice parameters and average A-site ionic radius, rA decrease linearly with x while the size disorder, as characterized by the variance, σ2, increases from 0.014 to 0.017 with x. As x is increased, the increase in σ2 drives a linear decrease in TC. The magnetic entropy change, ΔSM, for a field change of 1 T is obtained by magnetization measurements, giving a maximum value of 1.7 J/kg K, and a relative cooling power of 43 J/kg, independent of x. These results suggest that replacing lanthanum with a mixture of lanthanides is a realistic way to tune the working temperature of magnetocaloric manganites while maintaining a constant magnetocaloric effect.

Size-driven magnetic transitions in La1/3Ca2/3MnO3 nanoparticles

Magnetic properties of electron-doped La1/3Ca2/3MnO3 manganite nanoparticles with average particle size ranging from 12 to 42 nm, prepared by the glycine-nitrate method, have been investigated in temperature range 5–300 K and in magnetic fields up to 90 kOe. Reduction in the particle size suppresses antiferromagnetism and decreases the Néel temperature. In contrast to bulk crystals, the charge ordering does not occur in all studied nanoparticles, while a weak ferromagnetism appears above 200 K. Low temperature magnetic hysteresis loops indicate upon exchange bias effect displayed by horizontal and vertical shifts in field cooled processes. The spontaneous and remanent magnetization at low temperature shows a relatively complex variation with particle size. The size-induced structural/magnetic disorder drives the La1/3Ca2/3MnO3 nanoparticles to a pronounced glassy behavior for the smallest 12 nm particles, as evidenced by large difference between zero field cooled and field cooled magnetization, frequency dependent ac-susceptibility, as well as characteristic slowing down in the spin dynamics. Time evolution of magnetization recorded in magnetic fields after field cooling to low temperatures exhibits pronounced relaxation and a very noisy behavior that may be caused by formation of some collective states. Magnetic properties of the nanoparticle samples are compared with those of La0.2Ca0.8MnO3 nanoparticles. These results shed some light on the coupling between charges and spin degrees of freedom in antiferromagnetic manganite nanoparticles.

Size-dependent spin state and ferromagnetism in La0.8Ca0.2CoO3 nanoparticles

Magnetic and structural properties of nanocrystalline low-doped La0.8Ca0.2CoO3 cobaltites with particle size of 8, 13, 23, and 50 nm, prepared by the glycine-nitrate method, were investigated in temperature range 5–320 K, magnetic field up to 50 kOe and under hydrostatic pressure up to 10 kbar. With particle downsizing, a noticeable expansion of unit cell, with concomitant changes in the rhombohedral structure toward the cubic one was observed. It was found that the increased surface-disorder effect strongly suppresses the ferromagnetic state in La0.8Ca0.2CoO3 nanoparticles leading to a decrease, by factor of about 2, both in spontaneous magnetization, MS, and Curie temperature, TC, when particle’s size decreases from 23 to 8 nm. The effective magnetic moment μeff was found also to decrease distinctly due to the strong interdependence between Co–O–Co interactions and Co spin state. The size-induced magnetic disorder drives the La0.8Ca0.2CoO3 nanoparticles to a dominant glassy behavior for 8 nm particles. This is evidenced by the fact that the freezing temperature varies with magnetic field in a strict conformity with the de Almeida–Thouless law for spin glasses and also by the observation of characteristic slowing down in the spin dynamics. The applied pressure suppresses TC, MS, and coercive field HC, like it is observed for bulk La0.8Ca0.2CoO3. Nevertheless, in nanoparticles the pressure effect on TC is noticeably stronger, while HC diminishes with pressure much slower then in bulk material.

Effects of Preparation Methods on the Catalytic Performance of LaMn0.8Mg0.2O3 Perovskite for Methane Combustion

A perovskite-type composite oxide, LaMn 0.8 Mg 0.2 O 3 , was prepared by five methods, i.e., glycine-nitrate, sol-gel, co-precipitation, combustion synthesis, and hydrothermal treatment. The composites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, H 2 -temperature-programmed reduction, and N 2 adsorption-desorption isotherms. The catalytic activity of LaMn 0.8 Mg 0.2 O 3 toward methane combustion was evaluated. The results show that the different preparation methods and calcination temperatures greatly influence the textural structure, crystallite size, and different oxygen species within the LaMn 0.8 Mg 0.2 O 3 perovskite material. The perovskite catalyst synthesized by the glycine-nitrate method and calcined at 700 °C shows the best activity for methane combustion among the tested materials. Its T 50 (the reaction temperature at which 50% CH 4 is converted) is only ∼440 °C. This good catalyst performance can be attributed to the small crystallite size (12.4 nm), larger surface area (18.6 m 2 /g), and high concentration of surface Mn 4+ cations, which creates more flexible and reactive surface oxygen species.

Preparation of Porous NiO-Ce 0.8Sm 0.2O 1.9 Ceramics for Anode-supported Low-temperatureSolid Oxide Fuel Cells

Porous NiO-Ce0.8Sm0.2O1.9 (NiO-SDC) ceramics with homogeneous pore distribution were prepared using polystyrene (PS) spheres as pore templates. NiO-SDC powders were synthesized by a glycine-nitrate method, ultrasonically mixed with PS spheres in ethanol, dried and then pressed into green pellets. The pellets were sintered to yield porous NiO-SDC ceramics. The effects of the sintering temperature on the microstructure and mechanical strength of the ceramics were investigated. NiO-SDC ceramics sintered at 1200 and 1350°C have interconnected pore structures and high compression strength. When single cells were fabricated using porous NiO-SDC ceramics as anode-supported layers, the peak power density of the cells at 600°C was 333 and 353 mW·cm−2 for ceramics sintered at 1200 and 1350°C, respectively. The results indicated that these porous ceramic materials are promising for anode substrates for solid oxide fuel cells.

Size effect on the magnetic properties of antiferromagneticLa0.2Ca0.8MnO3nanoparticles

Magnetic properties of electron-doped ${\text{La}}_{0.2}{\text{Ca}}_{0.8}{\text{MnO}}_{3}$ manganite nanoparticles with average particle size ranging from 15 to 37 nm, prepared by the glycine-nitrate method, have been investigated in temperature range 5--300 K and in magnetic fields up to 90 kOe. A monotonous enhancement of weak ferromagnetism linked to the reduction in the particle size was observed for all nanoparticles. Magnetic hysteresis loops also indicate size-dependent exchange bias effect displayed by horizontal and vertical shifts in field-cooled processes. The magnetization data reveal two ferromagnetic components: first one appears at $T\ensuremath{\sim}200\text{ }\text{K}$ and may be attributed to surface magnetization and second one appears as a result of spin canting of antiferromagnetic core or is developed at some interfaces inside nanoparticles. Time evolution of magnetization recorded in magnetic fields after the field cooling to low temperatures exhibits a very noisy behavior that may be caused by formation of collective state of nanoparticles with no clear tendency to reach equilibrium state. Magnetic properties of the nanoparticle samples are compared with those of the bulk ${\text{La}}_{0.2}{\text{Ca}}_{0.8}{\text{MnO}}_{3}$.

Ni/SDC Materials for Solid Oxide Fuel Cell Anode Applications by the Glycine-Nitrate Method

NiO/Ce0.8Sm0.2O1.9 (NiO/SDC, 65wt.% NiO) composite powders were synthesized by a glycine-nitrate process (GNP) to fabricate Ni/SDC anode-supported solid oxide fuel cell (SOFC). The results show that the composite powders are composed of single cubic phases of NiO and SDC and have a particle size in nanometer range. NiO/SDC ceramics were prepared from the NiO/SDC powders and were converted into Ni/SDC cermets by reduction in H2, which were employed as anode materials for SOFC with SDC electrolyte. It is shown that Ni/SDC cermets from the NiO/SDC composite powders by the GNP have porous and homogeneous microstructures and show good electrical conductivity. A single SOFC based on Ni/SDC anode with about 50µm SDC electrolyte film and about 80µm La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode was constructed. Open circuit voltage (OCV) of the cell is about 0.8V and maximum power density is 361.42 and 394.78 mWcm-2 at 750 and 800°C, respectively.