scholarly journals Electrochemical Property Assessment of Pr2CuO4 Submicrofiber Cathode for Intermediate-Temperature Solid Oxide Fuel Cells

2016 ◽  
Vol 13 (1) ◽  
Author(s):  
Ting Zhao ◽  
Li-Ping Sun ◽  
Qiang Li ◽  
Li-Hua Huo ◽  
Hui Zhao ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Reduction Reaction ◽  
Intermediate Temperature ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Rate Limiting Step ◽  
Heat Treated ◽  
Porous Microstructure ◽  
Ft Ir ◽  
Property Assessment

The Pr2CuO4 (PCO) submicrofiber precursors are prepared by electrospinning technique and the thermo-decomposition procedures are characterized by thermal gravity (TG), X-ray diffraction (XRD), Fourier transform infrared spectoscopy (FT-IR), and scanning electron microscopy (SEM), respectively. The fibrous PCO material was formed by sintering the precursors at 900 °C for 5 hrs. The highly porous PCO submicrofiber cathode forms good contact with the Ce0.9Gd0.1O1.95 (CGO) electrolyte after heat-treated at 900 °C for 2 hrs. The performance of PCO submicrofiber cathode is comparably studied with the powder counterpart at various temperatures. The porous microstructure of the submicrofiber cathode effectively increases the three-phase boundary (TPB), which promotes the surface oxygen diffusion and/or adsorption process on the cathode. The PCO submicrofiber cathode exhibits an area specific resistance (ASR) of 0.38 Ω cm2 at 700 °C in air, which is 30% less than the PCO powder cathode. The charge transfer process is the rate limiting step of the oxygen reduction reaction (ORR) on the submicrofiber cathode. The maximum power densities of the electrolyte-support single cell PCO|CGO|NiO-CGO reach 149 and 74.5 mW cm−2 at 800 and 700 °C, respectively. The preliminary results indicate that the PCO submicrofiber can be considered as potential cathode for intermediate temperature solid fuel cells (IT-SOFCs).

Influence of Substrate Temperature in the Morphology and Microstructure of YSZ Films Obtained on LSM Porous Substrate via Spray Pyrolysis

2012 ◽  
Vol 727-728 ◽  
pp. 691-696 ◽  
Author(s):  
Tiago Falcade ◽  
Giselle Barbosa de Oliveira ◽  
Diego Pereira Tarragó ◽  
Vânia Caldas de Sousa ◽  
Célia de Fraga Malfatti
Keyword(s):  
Substrate Temperature ◽  
Spray Pyrolysis ◽  
Spray Pyrolysis Technique ◽  
Precursor Solution ◽  
Cubic Phase ◽  
Porous Substrate ◽  
X Ray Diffraction ◽  
Heat Treated ◽  
Ft Ir ◽  
Influence Of Substrate

Many studies have been reported in the literature related to YSZ films deposited on dense substrate or applied directly on the SOFC anode. However, there are not a lot of studies about the YSZ deposition on the cathode. The present work aims to obtain yttria-stabilized zirconia (YSZ), using the spray pyrolysis technique, for their application as electrolyte in solid oxide fuel cells (SOFC). The films were obtained from a precursor solution containing zirconium and yttrium salts, dissolved in ethanol and propylene glycol (1:1), this solution was sprayed onto a heated LSM porous substrate. The substrate temperature was varied in order to obtain dense and homogeneous films. After deposition, the films were heat treated, aiming to crystallize and stabilize the zirconia cubic phase. The films were characterized by Scanning Electron Microscopy (SEM), thermal analysis, X-ray diffraction and Fourier transform Infrared Spectroscopy (FT-IR).

Sintering Effects on LSCF Cathodes for Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFCs)

2010 ◽  
Vol 139-141 ◽  
pp. 141-144 ◽  
Author(s):  
Andanastuti Muchtar ◽  
Noorashina A. Hamid ◽  
Norhamidi Muhamad ◽  
Wan Ramli Wan Daud
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Sol Gel ◽  
Electrical Power ◽  
Reduction Reaction ◽  
Solid Oxide ◽  
Intermediate Temperature ◽  
Perovskite Oxide ◽  
Oxide Fuel ◽  
Research Attention

Solid oxide fuel cells (SOFCs) have been the centre of much research attention as these shows much potential in the generation of electrical power especially in terms of the high conversion efficiency of chemical energy to electric power. Recent research has been focused on a new material which is an electro catalyst for the oxygen reduction reaction in the intermediate temperature range (600-800oC). In this work, perovskite oxide which is a mixed ionic conducting material, La1-xSrxCo0.2Fe0.8O3-δ (LSCF) with x = 0.3-0.5 has been developed using the sol-gel method. The obtained powders were pelletized and sintered at different temperatures from 800 to1300oC. The sintered properties of the LSCF pellets such as density, porosity, grain size and shrinkage were investigated. A sintering temperature of 900oC was found to be the optimum temperature for the preparation of the LSCF cathodes in this study.

scholarly journals Synthesis of NiFe2O4 nanofibers by joint sol-gel and electrospinning technique

10.30544/387 ◽  
2018 ◽  
Vol 24 (3) ◽  
pp. 173-180
Author(s):  
Aleksandar Grujić ◽  
Vladan Ćosović ◽  
Jasna Stajić-Trošić ◽  
Aleksandar Ćosović ◽  
Mirko Stijepović ◽  
...  
Keyword(s):  
Elevated Temperatures ◽  
Sol Gel ◽  
Morphological Characteristics ◽  
Magnetic Behavior ◽  
Composition Analysis ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Web Structure ◽  
Crystallite Sizes ◽  
Ft Ir

In this study, electrospinning combined with sol-gel technique is applied in order to produce magnetic nickel ferrite (Ni-ferrite) nanofibers. The prepared Ni-ferrite gel was mixed with poly(vinylpyrrolidone) (PVP) solution which was used as a spinning aid to enable spinnability of the mixture. Structural and morphological characteristics of the as-spun ferrite gel/PVP composite web structure and calcinated Ni-ferrite nanofibers were analyzed using scanning electron microscopy (SEM). Phase composition analysis was carried out by Fourier-transform infrared (FT-IR) spectroscopy, X-Ray diffraction analysis (XRD) and 57Fe Mössbauer spectroscopy (MS). The obtained results suggest that the pure nanocrystalline NiFe2O4 dense mat to the almost coral-like structure of fibers with diameters ranging from hundreds of nanometers to few micrometers was obtained. The results of MS analysis revealed the existence of a crystallite size distribution within the material as well as the existence of a superparamagnetic fraction with very small crystallite sizes (<13nm). Magnetic behavior of the obtained material at elevated temperatures was also scrutinized using thermomagnetic measurements (TM) up to 800 °C.

Copper Doped Lanthanum Strontium Ferrite as Cathode for La0.8Sr0.2Ga0.8Mg0.2O3

2014 ◽  
Vol 93 ◽  
pp. 13-18
Author(s):  
Francesca Zurlo ◽  
Elisabetta di Bartolomeo ◽  
A. d’Epifanio ◽  
Valeria Felice ◽  
Isabella Natali Sora ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Cathode Material ◽  
Morphological Analysis ◽  
Electrochemical Impedance ◽  
Stoichiometric Composition ◽  
Reduction Reaction ◽  
Electrochemical Tests ◽  
Rate Limiting Step ◽  
Maximum Current ◽  
Rate Limiting

A “cobalt free” cathode material with stoichiometric composition La0.8Sr0.2Fe0.8Cu0.2O3 (LSFCu) was specifically developed for La0.8Sr0.2Ga0.8Mg0.2O3 (LSGM) electrolyte. The chemical stability with LSGM electrolyte was investigated by structural and morphological analysis. The electrochemical properties of LSFCu dense pellets were investigated in the temperature range 600–750°C by electrochemical impedance spectroscopy (EIS). LSFCu/LSGM/LSFCu symmetrical cells were prepared and Area Specific Resistance (ASR) values, directly depending on the rate limiting step of the oxygen reduction reaction, were evaluated. Fuel cells were prepared using LSFCu as cathode material on LSGM pellet and electrochemical tests were performed and compared to similar fuel cells prepared by using commercial La0.6Sr0.4Fe0.8Co0.2O3(LSFCo). The maximum current density and power density recorded for LSFCu and LSFCo were comparable demonstrating that Cu can be used as substitutes Co.

scholarly journals Use of Dendrimers during the Synthesis of Pt-Ru Electrocatalysts for PEM Fuel Cells: Effects on the Physical and Electrochemical Properties

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
J. C. Calderón ◽  
L. Calvillo ◽  
M. J. Lázaro ◽  
E. Pastor
Keyword(s):  
Fuel Cells ◽  
Direct Methanol Fuel Cells ◽  
Pem Fuel Cells ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Stripping ◽  
Ru Nanoparticles ◽  
Treatment Benefits ◽  
Heat Treated ◽  
Direct Methanol

In this work, Pt-Ru catalysts were synthesized by a novel methodology which includes the use as encapsulating molecules of dendrimers of different generation: zero (DN-0), one (DN-1), two (DN-2), and three (DN-3). Synthesized catalysts were heat-treated at 350°C, and the effects of this treatment was established from the physical (X-ray dispersive energy (XDE) and X-ray diffraction (XRD)) and electrochemical characterization (cyclic voltammetry and chronoamperometry). Results showed that the heat-treatment benefits the catalytic properties of synthesized materials in terms of CO and methanol electrochemical oxidation. The curves for CO stripping were more defined for heat-treated catalysts, and methanol oxidation current densities were higher for these materials. These changes are principally explained from the removal of organic residues remaining on the surface of the Pt-Ru nanoparticles after the synthesis procedure. After the activation of the catalysts by heating at 350°C, the real importance of the use of these encapsulating molecules and the effect of the generation of the dendrimer become visible. From these results, it can be concluded that synthesized catalysts are good catalytic anodes for direct methanol fuel cells (DMFCs).

Investigation of Y1-xCaxBaCo2O5+δ Cathodes for Intermediate-Temperature Solid Oxide Fuel Cells

2013 ◽  
Vol 830 ◽  
pp. 130-134 ◽  
Author(s):  
Wu Jie Ge ◽  
Qun Shao ◽  
Yan Zhi Ding ◽  
Xiao Yong Lu
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Single Phase ◽  
Solid Oxide ◽  
Intermediate Temperature ◽  
Ignition Process ◽  
Oxide Fuel ◽  
X Ray Diffraction ◽  
Auto Ignition ◽  
Maximum Conductivity

Double-perovskites Y1-xCaxBaCo2O5+δ(YCBC,x = 0.1-0.5) were synthesized with a auto ignition process and were assessed as cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCx) based on Sm0.2Ce0.8O1.9(SDC) electrolyte. X-ray diffraction confirms that there are some undesired peaks in YCBC0.1 and YCBC0.5, while the YCBC (x = 0.2-0.4) retains single phase with tetragonal structure. The YCBC materials exhibit chemical compatibility with SDC electrolyte up to a temperature of 1100°C. The conductivity of the samples decreases with increasing Ca content, and the maximum conductivity of YCBC is 506 Scm-1for x = 0.2 sample. The increased doping of Ca deteriorates the area-specific resistances of YCBC (x = 0.2-0.4) cathodes. The Rp values of YCBC cathodes at x = 0.2,0.3 and 0.4 on the SDC electrolyte are 0.26, 0.53 and 1.19Ωcm2at 650°C, respectively. This study suggests that YCBC0.2 can be potential candidates for utilization as IT-SOFCs cathode.

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