Formation energy of N 2 and NNH (in different geometries) on Au-based SAAs considering 3 d dopants. The shaded green area indicates the reaction energy, that is, the endothermicity of the hydrogenation of N 2 to NNH. By minimizing the shaded area, the reaction gets thermodynamically more favourable. Energies are referenced with respect to N 2 (g) and H adsorbed on Au.
