Figure 5: Ellingham and phase diagrams of the cobalt oxide and nickel oxide system.
From: Interrogation of bimetallic particle oxidation in three dimensions at the nanoscale
(a) Ellingham diagrams (a plot of Gibbs free energy versus temperature) of cobalt oxides and nickel oxides at one atmosphere pressure. The curves with dashed lines are Ellingham diagrams calculated using generalized gradient approximations (GGA). (b) The phase diagram of CoOx–NiOx system at one atmosphere pressure adapted from ref. 40. The areas shadowed in blue correspond to the reaction temperature and the Co atomic ratio in pristine particles relevant to our experiments.
