The decomposition of NO dimers on metal surfaces is a critical step in nitrogen oxide reduction technologies. In this study, we investigate the Cu(100) surface as a catalytic platform for this reaction using ab initio molecular dynamics (AIMD) simulations, based on density functional theory (DFT) with van der Waals corrections. A detailed analysis of the energy partitioning in the desorbed \(\hbox {N}_2\hbox {O}\) molecule reveals that the activation energy associated with N–O bond cleavage is primarily redistributed into the rotational mode, followed by the translational mode, and small fraction of the energy is transferred into vibrational excitation and dissipated into surface modes. This mode-specific energy redistribution suggests that enhancing the excitation of the rotational degree of freedom could improve the rate and efficiency of NO reduction. In addition, we evaluate the adsorption behavior of the reaction products, \(\hbox {N}_2\hbox {O}\) and atomic O, on Cu(100) using DFT calculations. \(\hbox {N}_2\hbox {O}\) is found to preferentially adopt a bent chemisorbed geometry, while atomic O favors adsorption at the fourfold hollow site. These stable configurations serve as the final state for the NO dimer decomposition pathway. While for the initial state is flat-ONNO dimer, which was discussed comprehensively in our previous work. Together, these results offer fundamental insights into the desorption dynamics, energy transfer mechanisms, and product–surface interactions that govern NO decomposition on copper catalysts, and may inform the rational design of more effective, non-PGM catalytic systems for environmental applications.
Graphical abstract
