Structure sensitivity of ammonia electro-oxidation on transition metal surfaces: A first-principles study

•Ammonia electro-oxidation mechanism was studied across 8 fcc metals using DFT.•We compare thermochemistry and kinetics across (111) and (100) facets.•Pt(100) is the most active surface owing to facile kinetics for N* removal.•Ir(100) follows in activity, followed by Pt(111) and Ir(111).•Improved catalysts should make deprotonation easier while keeping easy kinetics.