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 electro-catalysts; 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. (C) 2016 Elsevier B.V. All rights reserved.