Enhanced Anti-CO poisoning of platinum on mesoporous carbon spheres by abundant hydroxyl groups in methanol electro-oxidation

Abstract To date, substantial efforts have been made to improve the electrocatalytic performance and durability of Pt-based catalysts for the methanol oxidation reaction (MOR). However, these catalysts are still limited by their high susceptibility to poisoning due to strong COads adsorption on Pt surfaces. Herein, a new MOR catalyst is reported as a possible solution to this challenge. This catalyst features cobalt carbonate hydroxide (CoCH) nanorods that are intimately enclosed by Pt/Vulcan XC-72 carbon (Pt/C), wherein Pt nanoparticles with a diameter of ∼2 nm are uniformly decorated on Vulcan XC-72 carbon. Compared to Pt/C, CoCH–Pt/C exhibits impressive MOR activity and durability. More importantly, the CoCH–Pt/C catalyst can maintain 40% of its initial activity after 10,000 s of chronopotentiometry and can be fully reactivated by running several CV cycles in 1 M KOH. The incorporation of CoCH is believed to play a major role in facilitating the oxidative removal of COads at adjacent Pt sites, since it can readily promote water dissociation to form OHads in alkaline electrolytes. This finding was confirmed by CO-stripping, impedance spectra and CO poisoning experiments. The bifunctional interaction between Pt and CoCH provides a valuable reference for designing new high-performance MOR electrocatalysts.