Abstract
Anode layer, as the main site for the reaction of fuel and removal of byproducts, plays an important role in anode-supported solid oxide fuel cell (SOFC). Generally, high electrical conductivity and gas permeability (porosity) of the anode materials are required to reduce the polarization loss of SOFC. This study focuses on the manufacturing of porous anode layers for SOFC. The NiO/8YSZ cermets anode coatings are fabricated by atmospheric plasma spray (APS) using the blended powder of nickel coated graphite (Ni-graphite) after oxidation (NiO-graphite) and 8mol%Y2O3-stabilized ZrO2 (8YSZ). To increase the porosity and the uniformity of the coatings, nickel coated graphite with low density is used as the starting feedstock instead of the conventional pure Ni powder. To balance the conductivity (Ni), porosity (graphite), and structural stability (8YSZ) of the coatings, the effects of process parameters such as hydrogen (H2) gas flow rate, spraying distance, and pore formation precursor (carbon black addition) on the microstructures of resulting coatings by APS are investigated. The results show that the NiO/8YSZ anode coatings with high conductivity, structural stability and porosity could be deposited by APS with moderate H2 gas flow rate and short distance. The microstructure of the coating is mainly associated with the degree of melting of impact particles.
