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.