Preparation and characterization of NiO based nano-ceramic composites as alternative anode materials for solid oxide fuel cells (SOFCs)

Abstract

Solid oxide fuel cell (SOFC) is being developed all over the world at present as a future energy conversion device. The alternative anode materials are also being studied in order to develop efficient low temperature SOFCs (LTSOFCs) operating below 800o C. Ni‐based cermets are still the most promising anode materials and some targeted modifications are needed to improve the coking resistance and to enhance their electro-catalytic activity relatively at low temperature (~600 – 700 oC) range. Present work is aimed to develop alternate anode materials such as, NiO-Ce0.9Gd0.1O2-δ-Ce0.9Y0.1O2-δ, NiO-Ce0.8Gd0.2O2-δ-Ce0.8Y0.2O2-δ, NiO-Ce0.9Gd0.1O2-δ-Ce0.9Sm0.1O2-δ, NiO-Ce0.8Gd0.2O2-δ-Ce0.8Sm0.2O2-δ, NiO-Ce0.9Gd0.1O2-δ and NiO-Ce0.8Gd0.2O2-δ for by simple chemical precipitation route and characterize them towards application in SOFC systems. The precursor materials used in this synthesis were cerium nitrate hexahydrate, gadolinium nitrate, yttrium nitrate, samarium nitrate [as basic materials] and sodium hydroxide [as precipitator material]. C-TAB (cetyl trimethylammonium bromide) was used as a surfactant in order to avoid the agglomeration of the nanoparticles. The influence of Gd, Y and Sm doping on the phase structure development of ceria was investigated. The prepared anode materials were characterized by TGA, XRD, FTIR, particle size analysis, SEM and EDAX. The electrical characteristics of the materials were studied by electrochemical impedance spectroscopy. The results obtained were discussed in order to use the materials as alternate anode materials for SOFCs.