N2 is a remarkably inert molecule. The energy required to break one of its p bonds has been estimated to amount to approximately 110-120 kcal/mol, and consequently, gas-phase addition of a single H2 molecule is endothermic by almost 48 kcal/mol (though once the initial addition has taken place, further reduction to hydrazine becomes a downhill process). Furthermore, the gap between the highest occupied and lowest unoccupied molecular orbitals, HOMO and LUMO respectively, of N2 amounts to almost 10 eV, or 220 kcal/mol, and its proton binding energy, at 110 kcal/mol, is rather low, which renders stepwise reduction, based on individual electron and proton transfer steps, even more daunting. Despite these well-known challenges, nitrogen fixation is the primary source of organic nitrogen in plants, and by extension of most lifeforms on earth. Nowadays, > 50% nitrogen entering the biosphere stems from industrial N2 fixation, primarily through the (extremely energy intensive) Haber-Bosch (HB) process. Indirectly, the abundance of nitrogen feedstock, facilitated by the HB process, has played a pivotal role in ensuring food security around the world, and facilitated the exponential growth of the human population, from 2 to 9 billion over the past century and a half. While the benefits of the HB process to society can hardly be understated, it also carries a huge energy/carbon footprint: approximately 2% of worldwide energy production is spent for industrial nitrogen fixation. Therefore, there is a marked interest in developing more efficient catalysts for industrial ammonia synthesis, which can be operated at milder conditions.