Mo-triamidoamine complex as a promising catalyst for N2O reduction reaction: a DFT study

To address the environmental impact of greenhouse gas N2O, recent research has been increasingly focused on the development of single-atom catalysts (SACs). Herein, we explore the potential applications of Mo-triamidoamine complex [Mo-{(NHCH2CH2)3N}], henceforth termed as Mo-Tren, for the reduction of N2O, employing density-functional theory (DFT). The results reveal that Mo is energetically favorably anchored within the Tren cavity; in addition, the electronic properties emphasize the Mo atom as the active-site for catalysis. The N2O molecule demonstrates spontaneous dissociation on the catalyst surface when interacts through its O-end, releasing a dissociation energy of –4.63 eV. Contrarily, when N2O interacts via its N-end, it chemisorbs onto the Mo-Tren surface with the release of –2.13 eV as an adsorption energy (Ead). Further analyses of bond distances and adsorption energies reveal that CO and O2 molecules also chemisorb onto the Mo-Tren surface with energies of –3.07 eV and –3.87 eV, respectively. Since these values are lower than the (O-end) dissociation energy of N2O, it substantiates that the presence of CO and O2 do not interfere with the energetically feasible N2O reduction process. Moreover, the reaction pathway for CO + O* → CO2 was investigated for catalyst regeneration, showing that it proceeds rapidly on the Mo-Tren catalyst surface with an extremely low energy barrier (0.21 eV). This highlights the exceptional catalytic efficiency of Mo-Tren. These findings suggest that the designed catalyst has a significant potential for developing efficient solutions to mitigate the harmful N2O emissions into the environment. In this study, Mo-coordinated triamidoamine complex is investigated as a single-atom catalyst for the CO assisted N2O reduction reaction for the first time. The catalyst shows high reactivity towards the N2O reduction while for the catalyst recovery the CO oxidation procces proceeds via a small energy barrier.