(208h) The Challenge of CO Hydrogenation to Methanol: Fundamental Limitations Imposed By Linear Scaling Relations

Recent developoments in the theory of heterogeneous catalysis has made it possible to reduce the dimensionality of complex reaction networks to a few descriptors based on linear scaling relations^3,4. Here, we harness this knowledge to offer a novel description of the fundamental limits on the activity of synthesis gas conversion to methanol; a reaction that offers a sustainable route to obtaining value-added chemicals from CO₂/CO⁵. For CO hydrogenation, we have repeatedly shown before that the initial hydrogenation of CO* (* designates an adsorbed species) to CHO* is rate-limiting on terraces and steps of transition metals^6-9. Here, we show that there is a perfect linear correlation between the initial state energy and the transition state energy for this elementary step. Using a simple kinetic analysis, we cast this information into activity volcano plots with the effective activation energy and the initial state energy as independent variables. This analysis reveals the fundamental limits on activity imposed by the aforementioned scaling relation, and invites a vigorous search for novel materials that escape this linear scaling and offer improved activity towards CO hydrogenation to methanol.

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