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

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 CO_ads 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 CO_ads at adjacent Pt sites, since it can readily promote water dissociation to form OH_ads 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.