A DFT investigation of hydrazine nitrate dissociation mechanism on MoN(0 0 1)

Hydrazine nitrate (HN) is an important additive for hydrazine-based monopropellant. In this work, density functional theory (DFT) was adopted to calculate the decomposition process of HN components on MoN (0 0 1) catalyst surface. Firstly, two stable adsorption configurations of hydrazine nitrate were identified and determined the catalytic decomposition pathway of the thermodynamically favorable configuration. Pathway analysis revealed that the nitric acid group preferentially decomposes in all pathways. Moreover, due to the high activation and desorption energies, H2O molecules are more likely to be generated in the gas phase rather than preferentially adsorbed on the surface. By calculating the activation energies of each elementary reaction, it can be concluded that the cleavage of the NO bond in NO3– with the barrier energy of 0.32 eV plays a decisive role in the decomposition of the HN molecule.