Design Criteria\nfor Active and Selective Catalysts\nin the Nitrogen Oxidation Reaction

The direct conversion of dinitrogen to nitrate is a dream\nreaction\nto combine the Haber–Bosch and Ostwald processes as well as\nsteam reforming using electrochemistry in a single process. Regrettably,\nthe corresponding nitrogen oxidation (NOR) reaction is hampered by\na selectivity problem, since the oxygen evolution reaction (OER) is\nboth thermodynamically and kinetically favored in the same potential\nrange. This opens the search for the identification of active and\nselective NOR catalysts to enable nitrate production under anodic\nreaction conditions. While theoretical considerations using the computational\nhydrogen electrode approach have helped in identifying potential material\nmotifs for electrocatalytic reactions over the last decades, the inherent\ncomplexity of the NOR, which consists of ten proton-coupled electron\ntransfer steps and thus at least nine intermediate states, poses a\nchallenge for electronic structure theory calculations in the realm\nof materials screening. To this end, we present a different strategy\nto capture the competing NOR and OER at the atomic scale. Using a\ndata-driven method, we provide a framework to derive generalized design\ncriteria for materials with selectivity toward NOR. This leads to\na significant reduction of the computational costs, since only two\nfree-energy changes need to be evaluated to draw a first conclusion\non NOR selectivity.