(Y0.5In0.5)Ba(Co,Zn)4O7 cathodes with superior high-temperature phase stability for solid oxide fuel cells

► Cosubstitution of Y and In in (Y0.5In0.5)Ba(Co3Zn)O7 eliminates instability problems. ► Improved phase stability allows the incorporation of higher Co contents. ► Higher Co content is beneficial to realize good electrochemical performance.