Thermal stability, oxygen non-stoichiometry, electrical conductivity and diffusion characteristics of PrNi0.4Fe0.6O3−δ, a potential cathode material for IT-SOFCs

Vashook²,

Trots

et al. 2014

J Adv Ceram

Self Cite

p range. The oxygen exchange coefficients determined in reduction mode are higher than those determined in oxidation mode. This is explained by clusterization of oxygen vacancies on the surface of the sample investigated in oxidation mode. The opposite tendency is found for chemical diffusion coefficients. Unlike surface, the oxygen vacancies of the volume region are probably not clustered and have predetermined the higher oxygen diffusion mobility of the sample treated in oxidation mode.

Section: Oxygen Surface Exchange and Chemical Diffusion Coefficientscontrasting

confidence: 69%

Chemical diffusion and oxygen exchange of LaNi0.4Fe0.6O3−δ ceramics

Vashook²,

Trots

et al. 2014

J Adv Ceram

Self Cite

“…In another paper, on the contrary, a single PrNi 0.4 Fe 0.6 O 3 phase was obtained which was phase stable at P O2 > 1 Pa up to 1000 °C. [ 257 ] The oxygen diffusion coeffi cients of this PrNi 0.4 Fe 0.6 O 3 , determined by stepwise heating of the sample (reduction), were found to be higher than that determined by cooling of the samples (oxidation). They believed that it was likely the presence of neutral defect clusters of the type (B-oxygen vacancy-B) in PrNi 0.4 Fe 0.6 O 3 that reduced the amount of "free" oxygen vacancies.…”

Section: Review (11 Of 34) 1500537 Wileyonlinelibrarycommentioning

confidence: 81%

“…[256][257][258][259] The substitution of La by Pr in LaNiO 3 may help to mediate the reactivity of the electrode with YSZ electrolyte. Hashimoto et al totally replaced La in LNF with Pr and studied the viability of new PrFe 1− x Ni x O 3− δ ( x ≈ 0.4-0.6) as potential cathode materials.…”

Section: Review (11 Of 34) 1500537 Wileyonlinelibrarycommentioning

confidence: 99%

“…They believed that it was likely the presence of neutral defect clusters of the type (B-oxygen vacancy-B) in PrNi 0.4 Fe 0.6 O 3 that reduced the amount of "free" oxygen vacancies. [ 257 ] Lately, a PrNi 0.6 Co 0.4 O 3 perovskite material was developed and tested as an oxygen reduction electrode by mixing with SDC. [ 258 ] This composite had a low TEC of 13.49 × 10 −6 K −1 at 700 °C and a single cell with this composite as cathode showed a promising power output of 1.09 W cm −2 at 700 °C.…”

Section: Review (11 Of 34) 1500537 Wileyonlinelibrarycommentioning

confidence: 99%

See 1 more Smart Citation

Advances in Cathode Materials for Solid Oxide Fuel Cells: Complex Oxides without Alkaline Earth Metal Elements

Advanced Energy Materials

Zhou

Ding

et al. 2015

250

155

Solid oxide fuel cells (SOFCs) represent one of the cleanest and most efficient options for the direct conversion of a wide variety of fuels to electricity. For example, SOFCs powered by natural gas are ideally suited for distributed power generation. However, the commercialization of SOFC technologies hinges on breakthroughs in materials development to dramatically reduce the cost while enhancing performance and durability. One of the critical obstacles to achieving high‐performance SOFC systems is the cathodes for oxygen reduction reaction (ORR), which perform poorly at low temperatures and degrade over time under operating conditions. Here a comprehensive review of the latest advances in the development of SOFC cathodes is presented: complex oxides without alkaline earth metal elements (because these elements could be vulnerable to phase segregation and contaminant poisoning). Various strategies are discussed for enhancing ORR activity while minimizing the effect of contaminant on electrode durability. Furthermore, some of the critical challenges are briefly highlighted and the prospects for future‐generation SOFC cathodes are discussed. A good understanding of the latest advances and remaining challenges in searching for highly active SOFC cathodes with robust tolerance to contaminants may provide useful guidance for the rational design of new materials and structures for commercially viable SOFC technologies.

“…A single phase compositions in the system LaFe 1-x Ni x O 3 are known at x=0-0.8 [2,3] and in system PrFe 1-x Ni x O 3-δ at x=0.4-0.6 [1,4]. PrFe 0.7 Ni 0.3 O 3-δ was prepared and its crystal structure, conductivity and diffusion parameters were compared with analogous LaFe 0.7 Ni 0.3 O 3-δ composition at broad range of temperatures (20-1000°C) and oxygen partial pressures 0.6-21000 Pa).…”

Section: Introductionmentioning

confidence: 99%

Crystal structure, oxygen nonstoichiometry and diffusion mobility in some ferrites-nickelites

Vashook

Rebello

2012 IEEE International Conference on Oxide Materials for Electronic Engineering (OMEE)

et al. 2012

1 Abstract. Crystal structure, thermal expansion, oxygen non-stoichiometry, electrical conductivity and diffusion characteristics of two analogous LaFe 0.7 Ni 0.3 O 3-δ and PrFe 0.7 Ni 0.3 O 3-δ compositions were investigated depending on temperature (20-1000 °C) and oxygen partial pressure (0.6-21000 Pa). The found oxygen diffusion and oxygen exchange coefficients for the both compositions at similar conditions are near to each other and varied in the range of 1·10 -7 -1·10 -5 cm 2 ·s -1 and 5·10 -6 -1·10 -4 cm·s -1 , respectively.