Where Esurf is the surface energy, Eslab is the calculated energy of the slab, Ebulk is the energy (per atom) of the bulk structure, n is the number of atoms in a unit cell and A is the surface area of the slab. The slab with the lowest surface energy was then isolated and utilized for the final step of this screen. VASP was used in the DFT calculations of slab energies. The top two layers of atoms in each slab were allowed to relax for two steps while the bottom layers were frozen. A gamma-centered kpoint mesh with a density of 1000 k-points/number of unit cell atoms was generated for each material using Pymatgen . In each structural optimization step, the atoms in the top two layers were allowed to relax until the energy convergence criterion of 10 -5 eV and the force convergence criterion of 0.1eV Å -1 were met. Once the relaxation steps had been concluded, the positions of all atoms in each slab was fixed in order to evaluate the energy of the slab, where the tetrahedron method with Blöchl corrections was used to integrate the Brillouin zone . The energy cutoff used in these slab calculations was 400eV. The slab surface with the lowest surface energy was used to calculate the binding energies of the *O, *OH and *OOH intermediates.