Predicting and Comparing C–M and O–M Bond Strengths for Adsorption on Transition Metal Surfaces

Abstract

Understanding which surface properties control adsorption on metal surfaces has long been a primary goal in surface science and catalysis, for both fundamental and technological reasons. Moreover, for the purposes of designing catalysts for enhanced selectivity, it can be desirable to understand surface properties that lead to significant differences in adsorption energies of hydrocarbons and oxygenates. In this work, expressions for predicting adsorption energies of CH3 and OH are developed, based in part on screening a large number of possible predictors. These expressions include the d-band center, d-band filling, and matrix coupling element, which are well-known in the literature, as well as the relatively unstudied p-band center. These expressions are also applied to other adsorbates, including alkyls, alkoxides, C, O, and H, allowing elucidation of how the adsorbate structure affects the adsorption energy. While all alkyls behave similarly and all alkoxides behave similarly, there are significant di...