Adsorbed Carbon Monoxide‐Enabled Self‐Terminated Au‐Grafting on Pt₆ Nanoclusters for Enhanced Methanol Electrooxidation

Abstract The study presents the first example of an adsorbed carbon monoxide (CO) enabled self‐terminated Au‐grafting on triphenylphosphine (PPh₃) stabilized Pt₆ nanoclusters (NCs) (Pt₆ (PPh₃)₄Cl₅ NCs or Pt₆ NCs). Adsorbed PPh₃ ligands weaken the Pt‐CO bond enabling the self‐terminated Au‐grafting on Pt₆ NCs. The Au‐grafted Pt₆ NCs exhibit enhanced methanol electrooxidation (MOR) in acidic solutions. The surface is composed of a PtAu ensemble exhibiting enhanced MOR and CO tolerance due to the synergistic interaction of Pt with Au and PPh₃. The hydrogen underpotential deposition (H‐UPD) signal from a CO‐covered surface reveals the existence of free‐Pt sites on the PtAu ensemble causing higher MOR reactivity. The Au and PPh₃ ensure electrocatalytic activity of the NCs, depriving of them at anodic potentials results in “a death‐valley” trend.