A computational study of the effect of alloying additions on the stability of Ni/c-ZrO2 interfaces

Design of new anode materials for solid oxide fuel cells (SOFCs) demands the understanding of properties of Ni/cubic-(c-) ZrO2 interfaces. In this work, we investigate the effect of 9 alloying additions (Ag, Au, Cd, Co, Cu, Fe, Sn, Sb, and V) on the stability of Ni/c-ZrO2 interfaces. We provide an analysis of the impact of oxygen partial pressure on segregation/desegregation behavior of the dopants. Based on the performed calculations, we show that addition of Co, Fe, or V to the classical SOFC anode can improve its stability under typical SOFC operating conditions. We also predict that Ag, Au, Cd, Cu, Sn, and Sb alloying additions might increase the agglomeration rate of the metal particles. Nevertheless, at low doping concentrations and high anode porosity the negative effect might be minimized by segregation of alloying additions at a Ni surface. Predicted results are of significant interest for the design of bimetallic cermet for SOFC anode materials.