Two-dimensional metal-organic framework Mo3(C2O)12 as a promising single-atom catalyst for selective nitrogen-to-ammonia conversion

The development of single-atom catalysts (SACs) for the electrocatalytic nitrogen reduction reaction (NRR) remains a great challenge. Using density functional theory calculations, we design a new family of two-dimensional metal-organic frameworks [TM3(C2O)(12), TM = Sc-Au] and explore their feasibility as SACs for the NRR. The calculated adsorption Gibbs free energies of N-2 and NNH species demonstrate that only the Mo-3(C2O)(12) monolayer could both activate the N N bond and stabilize the adsorbed NNH intermediate. The Mo-3(C2O)(12) metal-organic framework not only possesses sufficient stability, but also exhibits high nitrogen fixation activity and substantial selectivity. The NRR distal pathway could achieve this sufficient goal with a low limiting potential of -0.36 V and a promising theoretical faradaic efficiency value of 100%. This work could give guidance to develop more effective NRR SACs using 2D metal-organic frameworks under ambient conditions.

Automated summary

This study designs a series of two-dimensional metal-organic frameworks as single-atom catalysts for the electrocatalytic nitrogen reduction reaction. Among them, the Mo-3(C2O)(12) monolayer shows the most promising performance, with sufficient stability, high nitrogen fixation activity, and substantial selectivity.