Figure 6: Optimized structures of H* adsorbed on nitrogen-doped graphene-encapsulated Co and RuCo alloys.

(a) Pure Co model (C239N1Co55), (b) Ru1Co alloy model (C239N1Ru1Co54) and (c) Ru2Co alloy model (C239N1Ru2Co53) (d) Ru3Co alloy model (C239N1Ru3Co52). The black, blue, pink, brown and white balls refer to C, N, Co, Ru and H atoms, respectively.