Perovskite and Composite Materials for Intermediate Temperatures Solid Oxide Fuel Cells
- PDF / 948,863 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 76 Downloads / 286 Views
1056-HH03-64
Perovskite and Composite Materials for Intermediate Temperatures Solid Oxide Fuel Cells T. Kharlamova1, S. Pavlova1, V. Sadykov1, T. Krieger1, N. Mezentseva1, V. Muzykantov1, G. Alikina1, A. Boronin1, V. Zaikovskii1, A. Ishchenko1, V. Rogov1, N. Uvarov2, J. Frade3, and Chr. Argirusis4 1 Boreskov Institute of Catalysis, Novosibirsk, 630090, Russian Federation 2 Institute of Solid State Chemistry SB RAS, Novosibirsk, 630128, Russian Federation 3 University of Aveiro, Aveiro, 3810-193, Portugal 4 Clausthal University of Technology, Clausthal-Zellerfeld, 38678, Germany ABSTRACT La0.8Sr0.2Fe0.6Ni0.4O2.9 (LSFN) and LSFN–La9.83Si4.5Fe1.5O26 (LSiF) nanocomposite were synthesized and investigated as cathode materials for intermediate temperature (IT) solid oxide fuel cells (SOFC). Phase and structure evolution with sample sintering temperature as well as their transport properties and catalytic activity in oxygen reduction were studied. INTRODUCTION SOFC offer pollution-free technology to generate electricity at high efficiencies. However, the reduction of SOFC working temperatures below 800°C appears to be crucial for their commercialization that necessitates the development of novel materials possessing high oxygen ion conductivity at respectively low temperatures [1]. In this view, apatite-type lanthanum silicates (ATLS) have recently attracted considerable attention as electrolytes for IT SOFC [2, 3]. Along with new electrolyte materials, the development of suitable anodes and cathodes is required to provide a good cell performance at rather low temperatures. Possessing high electrocatalytic activity, they must also have thermal expansion coefficient close to that of the electrolyte and be structurally and chemically stable, which increase interest to composite systems [1, 4]. Several lanthanum-nickel-iron mixed oxides with perovskite structure have been suggested as potential cathodes for IT SOFC [4-6]. However, studies devoted to the behavior of electrode materials in contact with ATLS electrolytes or that of ATLS-based composites are very scarce [7]. The present study is devoted to preparation and characterization of LSFN and LSFN– LSiF nanocomposite as cathode materials for IT SOFC. EXPERIMENTAL DETAILS LSFN perovskite and LSiF ATLS were synthesized by Pechini (Pe) method. Detailed description of the preparation technique is presented elsewhere [8, 9]. After polymeric precursor decomposition, the LSFN sample was ground with pestle and mortar and calcined at 700 ºC (1 h), 900ºC (5 h) and 1100ºC (3 h). LSiF was milled for 5 min in a planetary ball mill AGO and finally calcined at 900ºC for 5 h. For conductivity measurements, LSFN was pressed into pellets (d=15 mm, h=1 mm) under ~200 kgf/cm2 and calcined at 1100°C. To prepare composite (Comp), the mixture of LSFN calcined at 700°C and LSF calcined at 900°C with mass ratio 1:1 was ultrasonically dispersed in distilled water with addition of 1
wt% of polyethylene glycol as a surfactant using an Ika T25 ULTRA-TURRAX basic (IKA, Germany) generator. The dispe
Data Loading...
