New Strategies on SOFC
- PDF / 434,859 Bytes
- 9 Pages / 612 x 792 pts (letter) Page_size
- 33 Downloads / 189 Views
0972-AA10-01
New Strategies on SOFC Juan Carlos Ruiz-Morales1, Juan Peña-Martínez1, David Marrero-López1, Domingo Pérez-Coll1, Jesús Canales-Vázquez2, John T.S. Irvine3, and Pedro Núñez1 1 Department of Inorganic Chemistry, University of La Laguna, Avda. Astrofisico Fco. Sanchez, s/n, La Laguna, E-38200, Spain 2 Renewable Energy Research Institute, Albacete Science and Technology Park, Albacete, E02006, Spain 3 School of Chmistry, University of St Andrews, St. Andrews, KY16 9ST, United Kingdom
ABSTRACT Fuel Cells are highly promising energy conversion systems for the new energy scenario. Particularly, Solid Oxide Fuel Cells (SOFCs) have been extensively studied during the last few years as a result of the increasing interest in the development of more efficient, and environmentally friendly ways of energy generation, as well as a consequence of their fuel flexibility. This work shows some strategies to improve the efficiency of SOFCs through the use of new anode materials, a novel method of microstructural optimisation by means of polymeric templates, using composites or cermets-based materials or applying a new concept in SOFC, e.g. the Symmetrical SOFC (SFC). INTRODUCTION SOFCs are all-solid-state electrochemical devices that produce electricity with high efficiency (low emission of pollutants and low noise) from the electrochemical combination of a hydrogen-containing fuel and an oxidant such as oxygen [1]. The main components of these systems are a dense gas-tight solid electrolyte and porous electrodes to allow electrochemical reactions involving gas species and the transit of reagents and by-products to and from the active sites. Each single cell comprises two electrodes: an anode and a cathode separated by a gastight electrolyte. Since the gases reach each electrode compartment separately and the operation temperatures are relatively high, the materials must fulfil some general requirements: stability of the microstructure during both the preparation and the operation in a SOFC; chemical and physical compatibility and thermal expansion coefficients similar to those of the adjacent components; electrodes should have adequate porosity and catalytic activity to achieve the highest performances. The standard choice of materials [2] for a typical SOFC comprises: yttria-stabilised zirconia (YSZ) as electrolyte material; strontium-substituted lanthanum manganites (LSM) as the most common cathode material due to the high electrical conductivity at high temperature and good catalytic behaviour towards oxygen reduction; and finally Ni/YSZ cermet is the typical choice as anode material, as it offers excellent catalytic properties, mixed conductivity and good
current collection properties. However, such cermets present some disadvantages [3, 4] related to the low tolerance to sulphur, carbon build up when using hydrocarbon fuels and volume instability upon redox cycling. Another important and frequently forgotten issue concerns NiO toxicity. There exist a number of studies reporting illness associated to the inhalati
Data Loading...
