NiO-Ce0.9Gd0.1O1.95 Composites and their Cermets as Anode Materials for SOFC
Pp. 162-197 (36)
Allan J.M. de Araujo, Gabriel M. Santos, Joao P. de F. Grilo, Rubens M. do Nascimento, Carlos A. Paskocimas, Moisés R. Cesario and Daniel A. de Macedo
The anode of a Solid Oxide Fuel Cell (SOFC) is the component responsible
for releasing electrons. It must present some prerequisites such as porosity (30-40
wt.%) and mixed conductivity (ionic and electronic). To achieve that, it often consists
of a ceramic-metal composite (cermet) material. Ni-YSZ cermet is the material most
commonly used as anode SOFC, however it presents low electrochemical efficiency
below 750 °C. With this in mind, new materials have been studied, and Ni-GDC cermet
has shown promising results. This chapter focused mainly on a brief review of
NiO-Ce0.9Gd0.1O1.95 (NiO-GDC) composites and their Ni-GDC cermets as SOFC anode
materials. The chapter reports the history, concept, operation principle, reaction
mechanisms and components of SOFCs, addressing recent works in the field. The
synthesis of NiO-GDC composites by a one-step synthesis method (polymer-based
method) is compared with the conventional mechanical mixing method. Impedance
spectroscopy is shown to be a crucial technique to investigate the electrical properties
of SOFC functional materials. The chapter ends with a literature review on the
electrical properties of NiO-GDC composites and their cermets.
Impedance Spectroscopy, Microstructure, NiO-Ce0.9Gd0.1O1.95, NiOGDC,
Ni-GDC, One-Step Synthesis, SOFC, SOFC Anode.
Department of Materials Engineering, Federal University of Paraíba, João Pessoa, 58051-900, Brazil.