Surface X-ray Diffraction for the Characterization of Polymer Thin Films on Active Catalyst Surfaces

We propose using high-energy surface X-ray diffraction (HESXRD) to study model polymer/catalyst interfaces to understand the structural motifs occurring at an interface critical to the chemical recycling of plastic. Our results will enhance the atomic level understanding of the catalyst interface, in particular the surface relaxation and polymer coordination under reaction conditions. Short-chain hydrocarbons and polymer melts exhibit different reaction selectivity and activity, yet characterizing these interfaces has remained infeasible. Our previous experiments at ID31 show that HESXRD allows for the probing of the active catalyst under relevant conditions. We will apply similar methods to probe the polymer/Ru interaction and structure via the deposition of thin films. These insights will ultimately allow for a deeper understanding of the interface structure during polymer hydrogenolysis, allowing for the design of more efficient catalysts.