“…The following two strategies have been used: (1) Pt is coupled with other metals such as Ni [23][24][25][26], Au [8,27], Bi [28,29], Sb [30], and Rh [31], to prevent CO adsorption on the Pt surface through so-called ensemble and electronic effects, and (2) oxidative removal of adsorbed CO from the Pt surface is facilitated at low potentials by enriching the surface with oxygen-containing species via a bifunctional mechanism. This may be achieved by alloying Pt with oxophilic transition metals or metal oxides, such as NiO x [32][33][34][35], CoO x [32], Cu 2 O [36], FeO x [37], MnO x [38,39], and SnO 2 [40]. The presence of oxophilic materials, including Ni-oxy species, in the catalyst composition can assist with the electrochemical dissociation of water to form OHions at a more negative potential than that required for OHto be formed in the presence of bare Pt [32,[41][42][43].…”