Fig. 7: DFT-based Pt-Ni alloy SPDs concerning various state variables, derived by BEM-AL.
From: Rapid mapping of alloy surface phase diagrams via Bayesian evolutionary multitasking
The most stable Pt-Ni(111) surface configurations obtained after 9 DFT iterations are plotted in different colors in (a) β-a, (b) P-a and (c) T-a phase diagrams under the SMR condition of c = 0 with 2 of the 3 other state variable values: β = 2, P = 1 bar, T = 973 K. In the bottom half of the figure, the lower envelopes of the calculated surface free energies w.r.t. CH4 conversion under the SMR conditions of (d) c = 0 and (e) c = 100 ppm (both with β = 2, P = 1 bar, T = 973 K) are shown for the Pt-Ni(111), (100) and (311) surfaces after 9, 8 and 8 DFT iterations, respectively. The equilibrium nanoalloy shapes are obtained at CH4 conversions of 0.1 and 0.6 by Gibbs-Wulff constructions, where the facet colors are consistent with the corresponding lower envelopes.
