Adsorption of NO, NO2, pyridine and pyrrole on α-Mo2C(0 0 0 1): A DFT study

Density functional theory computations have been carried out on the adsorption of NO, NO2, pyridine and pyrrole on the α-Mo2C(0 0 0 1) surface for understanding the hydrodenitrogenation processes. On the Mo-terminated surface, NO decomposes into surface N and O, and NO2 dissociates into surface O and NO without any barriers, while the most stable adsorption modes of pyridine and pyrrole have π-face coordination over the three-fold molybdenum hollow sites with strongly destroyed aromatic systems. On the C-terminated surface, adsorbed surface species have been found for NO and NO2, while destroyed ring systems are found for pyridine and pyrrole. It is found that adsorption on the Mo-terminated surface is much stronger than that on the C-terminated surface.