Designing C3N-supported single atom catalysts for efficient nitrogen reduction based on descriptor of catalytic activity

The two-step strategy screening based high throughput calculation is an effective method to search for highly active single atom catalysts (SACs) for efficient nitrogen reduction reaction (NRR), sharing a common feature of active metal centers MN4. However, this method faces the lack of descriptor for designing SACs due to limited data. Herein we proposed a robust empirical rule to estimate 312 credible limiting potentials for NRR over 104 C3N-supported SACs. It is found that the limiting potential scales clearly with the adsorption free energies of two key reaction intermediates (∗N2H and ∗NH2), which are significantly dependent on the structure relating descriptor φ, and the activity of SACs with and without N coordination exhibits similar catalytic efficiency. We identified four high-performance SACs having moieties of CrC2N2, CrC4, MnC4 and OsC4 with high selectivity towards NRR and competitive limiting potentials of −0.40, −0.45, −0.53 and −0.54 V, respectively. The φ values for these four SACs are around 19–25 which fall within its optimal ranges of 20–25 validating its prediction fidelity. This work broadens the discovery of two-dimensional carbon-nitrides supported SACs free of N coordination towards efficient N2 reduction and opens a new route of descriptor-guided design of efficient SACs for electrocatalysis process.