Effects of zinc nitrate as a sintering aid on the electrochemical characteristics of Sr0.92Y0.08TiO3-δ and Sr0.92Y0.08Ti0.6Fe0.4O3-δ anodes

Although Sr0.92Y0.08TiO3-δ (SYT) and Sr0.92Y0.08Ti0.6Fe0.4O3-δ (SYTF) have been widely considered as promising materials for solid oxide fuel cell anodes, the poor densification restricts their commercial applications. As a sintering aid, zinc nitrate successfully stimulates the sintering process and improves densification. An investigation of linear shrinkage and scanning electron microscopy images indicated that the sinterability of SYT and SYTF materials was effectively improved by impregnating the green body with 5 mol% of Zn. It was found that the modification with zinc lowered the activation energy of the electrical conduction process and significantly improved the electrical conductivities of SYT and SYTF at all atmospheric conditions. The maximum power densities of the SYT and SYTF anodes were improved from 19.7 and 34.1 mW cm-2 to 56.9 and 92.3 mW cm-2 in H2 and from 10.2 and 19.4 mW cm-2 to 47.5 and 61.9 mW cm-2 in CH4, respectively.