DFT Study for Adsorption and Decomposition Mechanism of Trimethylene Oxide on Al(111) Surface

摘要

The adsorption and decomposition of trimethylene oxide (C3H6O) molecule on the Al(111) surface were investigated by the generalized gradient approximation (GGA) of density functional theory (DFT). The calculations employed a supercell (6 × 6 × 3) slab model and three-dimensional periodic boundary conditions. The strong attractive forces between C3H6O molecule and Al atoms induce the C-O bond breaking of the ring C3H6O molecule. Subsequently, the dissociated radical fragments of C2H6O molecule oxidize the Al surface. The largest adsorption energy is about −260.0 kJ/mol in V3, V4 and P2, resulting a ring break at the C-O bond. We also investigated the decomposition mechanism of C3H6O molecules on the Al(111) surface. The activation energies (Ea) for the dissociations V3, V4 and P2 are 133.3, 166.8 and 174.0 kJ/mol, respectively. The hcp site is the most reactive position for C3H6O decomposing.