Functional link between surface low-coordination sites and the electrochemical durability of Pt nanoparticles

Abstract

A promising strategy for achieving enhanced catalytic activity involves the use of nanoscale electrocatalysts; however, their low stability remains a major challenge. Among the various performance-degradation mechanisms, atomic dissolution is known to cause severe nanoparticle deactivation. To date, the factors influencing these catalysts' durability are not understood. Herein, we assess the role of low-coordination surface sites, focusing on the atomic dissolution of Pt nanoparticles. The density of low-coordination sites was finely controlled, and no significant size change occurred. Based on our findings, we suggest that the initial low-coordination sites trigger metal dissolution, which subsequently accelerates Pt dissolution. We believe that controlling the surface coordination number can open new routes for the design of highly durable nanoscale electrocatalysts.