Figure 16.

Top view of the slab models used to describe a) Mo₂TiC₂O₂ and b) Mo₂TiC₂O₂–Pt_SA. Atoms in blue, purple, green, brown, and red represent Ti, Mo, Pt, C, and O, respectively. c) Calculated charge density distribution differences between Mo₂TiC₂O₂ and Mo₂TiC₂O₂–Pt_SA.The isosurface value is 0.01 e A⁻³ to better plot the differences. d) Calculated PDOS of Mo₂TiC₂O₂ and Mo₂TiC₂O₂–Pt_SA, with aligned Fermi level. e) Calculated free energy profiles of HER at the equilibrium potential for Mo₂TiC₂O₂, Mo₂TiC₂O₂–Pt_SA and Pt/C. Reproduced with permission.29 Copyright 2018, Nature Publishing Group.