A Mo-salicylaldehyde-linker (Mo-Tp) based 2D MOF as a single-atom catalyst for the nitrogen reduction reaction

Two-dimensional (2D) materials for the electrocatalytic nitrogen reduction reaction (NRR) can offer a groundbreaking and sustainable alternative to the traditional Haber-Bosch process. Two-dimensional metal-organic frameworks (2D MOFs) have the potential to serve as single-atom catalysts (SACs), enabling the utilization of active metal centers up to 100% in the eNRR and also capable of reducing the HER effectively. This work outlines the screening of a new series of TM-Tp 2D MOFs (where Tp = 1,3,5-triformylphloroglucinol; TM = Cu, Ni, Cr, Mo, Os, Ru, and W) for the NRR, using density functional theory. Two screening stages based on the activation of the N₂ molecule and stabilization of the NNH intermediate showed that the Mo-Tp MOF monolayer is the most viable catalyst to be studied further. Mo-Tp shows outstanding stability and high potency towards being an efficient NRR catalyst with high selectivity. An investigation of the NRR pathway showed a limiting potential (U_L) of −0.38 V in the distal pathway. Furthermore, the theoretical faradaic efficiency (FE_t) is 100% towards the NRR. Our findings show that Mo-based 2D MOFs exhibit outstanding performance as NRR catalysts.