High-throughput computational screening of doped transition metal oxides as catalysts for nitrogen reduction

Developing sustainable methods for ammonia synthesis is important to combat rising global carbon emissions. An alluring possibility is the electrochemical reduction of nitrogen in an aqueous electrolyte, driven by renewable energy, but a suitable catalyst has remained elusive. Herein, we present the results of a large-scale computational screening study of the catalytic properties of over 800 doped transition metal oxides. Using activity and selectivity descriptors, we identify MoO2-based materials that could possibly catalyze ammonia synthesis, likely along with hydrogen evolution. MoO2 doped with tungsten is the most promising candidate, with predicted limiting potentials ranging from −0.5 to −1.1 V. However, further analysis suggests that hydrogen evolution is likely to be dominant in most cases. By establishing a set of screening criteria, we further provide a framework for future screening studies of doped materials.