Oxygen spillover on supported Pt-cluster for anti-CO-poisoning hydrogen oxidation.

The development of proton exchange membrane fuel cells (PEMFCs) is hindered by the need to reduce platinum (Pt) loading in the anodic hydrogen oxidation reaction (HOR) while increasing mass activity and CO tolerance. To address this challenge, researchers have designed a novel electrocatalyst consisting of 1.7 wt% Pt clusters loaded on a unique hollow bowl-like W3O/WC heterostructure. This design aims to enhance the anti-CO-poisoning HOR, which is crucial for improving the performance and durability of PEMFCs. The W3O/WC heterostructure plays a critical role in this design, as it enables electron delocalization, which helps to lower the HOR barrier and accumulate hydroxyl radicals (•OH) that accelerate CO oxidation. The electrocatalyst's unique properties arise from the interaction between the Pt clusters and the W3O/WC heterostructure. The Pt-O bond, formed through the oxygen spillover effect of W3O, promotes both hydrogen and CO oxidation. Additionally, the lattice-O consumed in W3O is replenished through water dissociation, ensuring a sustainable and efficient catalytic process. As a result, the electrocatalyst exhibits impressive performance, with a mass activity of 469 A g-1 at 50 mV and remarkable anti-toxicity even at high CO concentrations (2000 ppm). When integrated into a proton exchange membrane electrolytic cell (PEMEC), the electrocatalyst enables the device to achieve a peak power density of 1.63 W cm-2 while maintaining considerable resistance to CO poisoning. These findings suggest that this novel electrocatalyst design has significant potential for advancing the development of PEMFCs and improving their overall performance. Link: https://pubmed.ncbi.nlm.nih.gov/40274767/