Theoretical Insights into the Selective Electrocatalytic Reduction of NO to NH3 on a Two-Dimensional Cu-Benzylthiol Metal–Organic Framework Nanostructure

The electrocatalytic NO reduction reaction (NORR) is recognized as an appealing approach for NO removal, concurrently offering NH3 synthesis potential. To achieve the selective catalytic reduction of NO, the development of high-performance catalysts is crucial. In this study, we systematically investigate the reaction mechanism, product selectivity, and influence of solvent effect of electrocatalytic NORR using a 2D Cu-benzylthiol (Cu-BHT) metal–organic framework monolayer nanostructure through density functional theory (DFT) calculations. The investigation reveals that the NORR prefers the Mixed-2 pathway on the Cu-BHT monolayer nanostructure surface, marked by its complete exothermicity and a low activation barrier of only 0.32 eV. In addition, the Cu-BHT monolayer nanostructure exhibits a remarkable selectivity for the NORR, favoring NH3 production over N2, N2O, and H2. Comparative analysis with the existing literature solidifies the excellence of the Cu-BHT monolayer nanostructure as a superior NORR electrocatalyst. Additionally, a detailed examination of the charge redistribution highlights the influence of electron transfer on the hydrogenation site selectivity and, consequently, the entire reaction processes. This analysis also underscores the importance of catalyst composition to electrocatalytic NORR. Overall, by demonstrating the strategy to identify the optimal reaction pathway from both thermodynamic and kinetic perspectives, this study establishes TM-BHT, represented by Cu-BHT, as a promising platform for the development of more efficient electrocatalysts for NORR to NH3.