Oxygen Exchange in Pr2NiO4+δ at High Temperature and Direct Formation of Pr4Ni3O10−x

Oxygen permeability, stability and electrochemical behavior of % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaci % GGqbGaaiOCamaaBaaaleaacaaIYaaabeaakiaab6eacaqGPbGaae4t % amaaBaaaleaacaaI0aGaey4

“…On the contrary, Pr 2 NiO 4þd was reported to exhibit the highest oxygen tracer diffusion coefficients in Ln 2 NiO 4þd series [5]. These contradictions may result from thermodynamic metastability of the K 2 NiF 4 -type praseodymium nickelate phase at temperatures below 1123 K in oxidizing atmospheres, where Pr 2 NiO 4þd decomposes into the Ruddlesden-Popper type Pr 4 Ni 3 O 10 and Pr 6 O 11 [7]. Note that the segregation of praseodymium oxide, having a high catalytic activity in electrochemical reactions involving gaseous oxygen, may be advantageous for the SOFC cathode applications [10].…”

“…Solid solutions based on rare-earth nickelates with K 2 NiF 4 -type structure, A 2 NiO 4AEd , are a promising group of mixedconducting materials with potential applications for the cathodes of intermediate-temperature solid oxide fuel cells (IT SOFCs) and oxygen-separation membranes [1][2][3][4][5][6][7][8][9][10][11]. For these systems, the maximum emphasis in literature was focused on lanthanum nickelate, La 2 NiO 4þd .…”

Flame Spray Synthesis of Nanoscale La0.6Sr0.4Co0.2Fe0.8O3–δ and Ba0.5Sr0.5Co0.8Fe0.2O3–δ as Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

“…From an economic point of view, many metal-organic based precursors are excluded for large-scale processing; even more, when the compositions consist of more 'exotic' and hence expensive lanthanides (e.g. Sm, Pr or Nd), as they came up recently [21,22]. This paper is focussing on two interesting mixed ionicelectronic conductive (MIEC) cathode compositions, which are needed to realise a successful intermediate temperature SOFC technology at 600°C.…”

Структура, стабильность и термомеханические свойства Ca-замещенного Pr-=SUB=-2-=/SUB=-NiO-=SUB=-4+delta-=/SUB=-

“…• C происходит разложение Pr 2 NiO 4+δ с образова-нием Pr-содержащих примесей [13]. Это приводит к быстрому старению электродов на его основе, особенно в режиме топливного элемента [14].…”

“…5, a, b). Полу-ченные результаты согласуются с данными работы [13], в которой также отмечено образование упомянутых примесей в порошке состава Pr 2 NiO 4+δ , подвергнутом высокотемпературной обработке. Са-обогащенные мате-риалы (как с орторомбической, так и с тетрагональной структурой) характеризуются высокой термодинамиче-ской устойчивостью и не разлагаются после долговре-менной выдержки при 850…”