Nd-nickelate solid oxide fuel cell cathode sensitivity to Cr and Si contamination

► Sr-free Nd1.95NiO4+d cathode composition does not prevent from Cr-poisoning in SOFC. ► Electrochemical reduction of CrVIg to CrIIIs on Nd-nickelate induces Cr-poisoning. ► Si contamination in Nd1.95NiO4+d leads to insulating Nd-silicate formation. ► At the interface of Nd1.95NiO4+d with Ce0.9Gd0.1O1.95 an Nd-cerate reaction layer is formed. ► Secondary Nd-phase formations trigger Nd-nickelate decomposition into NiO.