A comparison of the transport properties of La2−xSrxNi1−yFeyO4+δ where 0<x<0.2 and 0<y<0.2

Abstract

Abstract.Recently there has been substantial interest in optimising perovskite type ceramics as mixed ionic-electronic conductors (MIECs) for use in ceramic oxygen generators and solid oxide fuel cells. However these materials suffer from thermomechanical deficiencies and therefore there is a need to develop alternative materials.Using the IEDP/SIMS technique the La2_xSrxNil-yFeyO4+8 series of compounds has been investigated and the oxygen tracer diffusion and surface exchange coefficients determined. It has been found that the oxide ion diffusivity of the x and y = 0 material is very close to that of the fast oxide ion conducting perovskites such as Lal_xSrxCoO3 (LSC) but on acceptor doping with Sr a considerable decrease in the oxygen tracer diffusion coefficient was observed. Further studies on the effects of B site doping, where y > 0, indicate that this has very little effect on the transport properties.

Intermediate Temperature Anode‐Supported Fuel Cell Based on BaCe0.9Y0.1O3 Electrolyte with Novel Pr2NiO4 Cathode

“…Previous studies have shown that mixed ionic electronic conductors (MIECs) such as Ln 2 NiO 4 (Ln = Pr, La, Nd) are good candidates as cathode materials for PCFC. They exhibit good electronic conductivity due to the metal mixed valency, good ion transport properties due to the oxygen over-stoichiometry [12][13][14][15][16][17] and the oxygen diffusion in Pr 2 NiO 4 is the highest among these materials [16]. This study deals with the fabrication and the characterisation of an anode-supported planar PCFC based on a thin proton conducting yttrium-doped barium cerate electrolyte and a novel MIEC-type praseodymium nickelate cathode material.…”

Evaluation of LaxSr2−xFeO4 layered perovskite as potential electrode materials for symmetrical solid oxide fuel cells

“…Most of the compounds with K 2 NiF 4 structure have the ability to accommodate large amount of M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 3 interstitial oxygen ions or generate loss of oxygen vacancies. These advantages make Ln 2 MO 4 as good candidates as cathodes for SOFCs [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. However, only La 0.6 Sr 1.4 MnO 4 was reported to be a promise anode for SOFCs [28] and potential symmetrical electrode for SSOFCs [29] which showed a maximum power density of 59 mW cm -2 at 800 0 C (H 2 as a fuel).…”

Design and processing parameters of La2NiO4+δ-based cathode for anode-supported planar solid oxide fuel cells (SOFCs)

“…Up to now, most of research works on LNO have been focused on basic properties, such as crystal structure [18], ionic/electronic transport [20,22,31,35], conduction mechanism [36,37], surface exchange [23,38], oxygen non-stoichiometry [33,39,40] and defect structure [41,42], rather than its practical applications. Moreover, upon implementation in the electrochemical cells, its electrode performance toward oxygen reduction reaction has often fallen short of the expectations based on its attractive characteristics as an alternative cathode [43e45].…”

“…The ionic transport in LNO occurs via complex mechanisms involving the diffusion of interstitial oxygen ions in the rock salt layer and oxygen vacancies in the perovskite planes [20,21]. Due to the fast conduction pathways for oxygen ions provided by the highly mobile oxygen interstitials [22], the bulk oxygen diffusion coefficient of LNO is considerably higher than those of conventional perovskite cathodes with vacancy diffusion mechanisms [23,24]. The LNO exhibits p-type electronic conductivity because the interstitial oxygen anions are chargecompensated by the generation of holes located on nickel ions in the perovskite layer [25,26].…”