Electrocatalytic decomposition mechanism of hydroxyamine nitrate on the Cu(111) surface

Hydroxylamine nitrate (HAN)-based electrically controlled solid propellants are currently the mainstream electrically controlled solid propellants. To gain a deeper understanding of their electrically controlled combustion mechanisms, this study employed quantum chemical simulations to systematically explore the electrocatalytic decomposition of HAN on a Cu(111) surface. The findings indicate that the electrocatalytic decomposition of NO3- ions on the anode surface is the dominant reaction for O2 generation, with a reaction barrier significantly lower than that of water electrolysis, demonstrating a pronounced reaction advantage. By optimizing the configurations of adsorbed molecules during the reaction and calculating the barriers for each reaction step, we have detailed the mechanism of HAN’s electrocatalytic decomposition on the Cu(111) surface. Additionally, the reaction on a cathode surface is relatively facile, with the key step being the adsorption and decomposition of NH3OH+ ions on the cathode surface. The generation of hydrogen ions in the anode reaction and their consumption in the cathode reaction lead to the cathode solution becoming alkaline and the anode solution becoming acidic after electrolysis. These findings provide important theoretical insights into the electrically controlled combustion mechanisms of HAN-based electrically controlled solid propellants.