Iron Diboride (FeB2) for the Electroreduction of NO to NH3

We report iron diboride (FeB2) as a high-performance metal diboride catalyst for electrochemical NO-to-NH3 reduction (NORR), which shows a maximum NH3 yield rate of 289.3 μmol h-1 cm-2 and a NH3-Faradaic efficiency of 93.8% at -0.4 V versus reversible hydrogen electrode. Theoretical computations reveal that Fe and B sites synergetically activate the NO molecule, while the protonation of NO is energetically more favorable on B sites. Meanwhile, both Fe and B sites preferentially absorb NO over H atoms to suppress the competing hydrogen evolution.