High-throughput screening and rational design to drive discovery in molecular water oxidation catalysis

Abstract

The difficulty of the oxygen evolution reaction (OER) is a fundamental impediment to the sustainable production of hydrogen, in which molecular catalysts show the most impressive activity in terms of turnover frequency. Here, we interrogate 444 automatically generated molecular water oxidation catalysts composed of well-known ligand scaffolds and 6 different transition metals (Cr, Mn, Fe, Ru, Co, and Ni). These data confirm the method-independent universal scaling relationship for water oxidation catalysts, describe routes toward circumventing this relationship, and justify the ascendency of Ru catalysts for this reaction. Leveraging this information while applying catalyst design principles, we summarize experimental results, giving credence to our prediction of 9 earth-abundant molecular catalysts with theoretical overpotentials ranging from 200 to 400 mV as promising leads for experimental investigation. We also establish insights into spin-dependent scaling relations for key OER intermediates. Altogether, this work outlines the first steps toward enabling inverse design for molecular OER catalysts. Generate total of 444 OER catalysts by combining well-known ligands and low-cost metals Demonstrate functional-independent scaling relations Establish metal-specific scaling relations and their implications Identify three Cr-based complexes as promising molecular OER catalysts Green hydrogen production could see widespread adoption if cost-effective catalysts for the oxygen evolution reaction were developed. Here, Craig et al. report a high-throughput screening of complexes generated by combining established ligands and low-cost metals, thereby identifying candidate catalysts for experimental realization and providing guidance for future studies.