Abstract
The present chapter starts out with introducing selected aspects of the theory of solid mechanics into a phenomenological description of the electrode/electrolyte system. Solid mechanics analyzes the stress and the elastic deformation within a solid body at equilibrium, subject to the action of external forces. At first sight, this description offers no link to chemical reaction kinetics. Why, then, introduce the subject of mechanics in a treatise of catalysis? The answer to that question resides in the link between the mechanical deformation of solid substrates–as parameterized by their strain”–and the energetics of adsorption. The reactions of heterogeneous catalysis
take place in an ensemble of adsorbed species. Adsorption enthalpies govern the population of these species and they are inherently linked to the energies of the transition states. Recent research has provided compelling evidence that even small elastic strain of the substrate may strongly impact the adsorption enthalpy. This opens
the perspective of tuning the elastic deformation–in other words, tuning the lattice parameter–of catalysts for enhancing their reactivity and/or for gaining insights into the microscopic details of the reaction.
