Figure (a) also shows the computed redox potential on the melamine-modified Pt(111) surface compared to those on the near-surface alloys. The melamine modification leads to a 0.12 V upward shift of the redox potential, indicating that OH adsorbate is destabilized by melamine. This result is consistent with the experimental cyclic voltammograms, which showed a reduction in the amount of OH* on both melamine-modified Pt nanoparticles and single-crystal surfaces. Experimentally, it was unclear whether this reduction was due to a reduction in hydroxyl adsorption sites caused by melamine or a change in the hydroxyl affinity of the surrounding active sites near melamine. Our simulation clearly demonstrates that the reduction is indeed caused by the latter mechanism.