Mixed ionic electronic ysz/ni composite for sofc anodes with high electrical conductivity.

• Grant number: 06/01761-1
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: June 01, 2006
• End date: November 30, 2006
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Fabio Coral Fonseca
• Grantee: Fabio Coral Fonseca
• Host Institution: Instituto de Pesquisas Energéticas e Nucleares (IPEN). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

The preparation, by a modified liquid mixture technique, of the composite ZrO2:8 mol% Y2O3 / NiO (YSZ / NiO) in a wide range of relative volume fraction is reported. Nanometric NiO particles dispersed over the YSZ have been achieved, resulting in dense sintered specimens with no solid solution formation between the oxides. Such a feature allowed for the electrical characterization of the composites in a wide range of temperature and oxygen partial pressure. The main results indicate that the composites have high electrical conductivity and the transport properties in these mixed ionic electronic (MIEC) composites are strongly dependent on the relative volume fraction of the phases, microstructure, and temperature. These parameters should hence be taken into consideration for the optimized design of MIEC composites for electrochemical applications. In this context, the composite was reduced under H2 for the preparation of high-conductivity YSZ / Ni cermets for using as solid oxide fuel cell (SOFC) anode material with relatively low metal content. (AU)