“…[7,8] Combinatorial exploration of vast alloy composition spaces has been actively used as at ool in experimental catalyst discovery for av ariety of reactions and constituent elements, [9][10][11][12][13][14][15][16] and efficient sampling of catalyst materials has also progressed. [17] However,a st he number of constituent elements increases,t he number of possible compositions grows combinatorially large and individual point testing cannot be accomplished within realistic time scales (see Modeling the catalytic activity of highly diverse and complex surfaces is still in its infancy with only af ew studies conducted, [1,3,4,20,21] and modeling of other aspects relevant for catalysis,such as surface stability under reaction conditions,is also being investigated. [22,23] We propose away to estimate the number of experiments needed using am odel that has been found to correctly predict experimental trends for electrocatalytic ORR across hundreds of different alloy compositions within the Ag-Ir-Pd-Pt-Ru system.…”