Flame Spray Synthesis of Nanoscale La_0.6Sr_0.4Co_0.2Fe_0.8O_3–δ and Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3–δ as Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

Abstract

Electrochemical performance and degradation was analysed by conductivity measurements as well as thermogravimetric analysis (TGA) under different atmospheres. CO2 was identified as a critical parameter in terms of carbonate formation from Ba0.5Sr0.5Co0.8Fe0.2O3–δ and causes a strong increase in the material resistivity, whereas La0.6Sr0.4Co0.2Fe0.8O3–δ is unaffected. The oxygen exchange kinetic of both compositions is affected by CO2 containing atmospheres.

The Rheology of Stabilised Lanthanum Strontium Cobaltite Ferrite Nanopowders in Organic Medium Applicable as Screen Printed SOFC Cathode Layers

“…The electrolyte (CGO) pellets, being substrates for printed cathodes, were pressed by uniaxial pressing (PW 20, PaulOtto Weber GmbH) in a cylindrically shaped mould under a pressure of 15 MPa and were later sintered at 1,550°C for 4 h. LSCF powders were prepared by spray pyrolysis [20] and flame spraying [21] resulting in submicron and nanosized materials, respectively. The powder properties are described in Table 1.…”

Flame spray deposition of La0.6Sr0.4CoO3−δ thin films: Microstructural characterization, electrochemical performance and degradation

“…Due to the mixed conductivity, volume diffusion occurs in addition to surface diffusion and accelerates the oxygen transfer kinetics of these MIEC perovskites compared to LSM [5]. Among these perovskites the lanthanum strontium cobaltite reveals a higher structural stability compared to BSCF, which decomposes for residual CO 2 contamination from the air during cathode operation [8,10,12].…”

“…In latter reference the deposition mechanism has been investigated in detail. The advantages of this method include the very high deposition rates of about 30 nm min −1 compared to other thin film processes, which are limited to a few nm min −1 and the low deposition temperatures of 200 • C. Furthermore, no vacuum is required for the deposition, it is easy to scale-up and it is possible to coat large areas with low processing cost [8].…”

“…Particularly for the YSZ/LSM system, the reduced performance is assigned mainly to the surface-dominated oxygen transfer kinetics of the purely electronic conducting LSM cathode [5]. Therefore, alternative materials with mixed ionic-electronic conductivity (MIEC) have been investigated, such as La 1−x Sr x CoO 3−ı (LSC) [6,7], La 1−x Sr x Fe 1−x Co x O 3−ı (LSCF) [8,9], Ba 1−x Sr x Fe 1−x Co x O 3−ı (BSCF) [8,[10][11][12][13][14][15], and Ba 1−x Sr x Fe 1−x Zn x O 3−ı [14,16]. Due to the mixed conductivity, volume diffusion occurs in addition to surface diffusion and accelerates the oxygen transfer kinetics of these MIEC perovskites compared to LSM [5].…”

Flame spray synthesis of nano lanthanum strontium manganite for solid oxide fuel cell applications

“…In liquid-fed flame synthesis the use of non-volatile type precursors makes the process cheaper and more versatile. Although several other cathode materials have been recently synthesized by the flame route [11,12], not much literature is available in case of flame synthesis of LSM except that of Charojrochkul et al [13] that resulted in micron-sized particles.…”