Monday, 2 October 2017: 14:20
Chesapeake K (Gaylord National Resort and Convention Center)
The purpose of this work is to explore the concept and properties of a novel design for Pt based catalysts. Highly porous Ni foam capped with a layer of graphene was utilized as a substrate for layer by layer Pt growth through a surface-limited redox replacement (SLRR) scheme. A survey of literature reveals seems to indicate that ours is the first instance of graphene/metal-foam being used as a template for the electrochemical deposition of Pt wetted few-monolayer films. Based on XPS, CV, SEM/EDS and high-resolution TEM analysis, it has been shown that the graphene deposition covers much of the Ni foam and that the Pt subsequently grows epitaxially on the graphene. This scheme leads to Pt utilization that approaches theoretical limits. This catalyst synthesis approach may prove extremely valuable for high-utilization and low-loading catalyst applications. We present here a thorough investigation of the atomic/electronic structure and of the related evolution of electrocatalytic properties as a function of the graphene-templated layer-by-layer growth.