A DFT study of methane activation on graphite surfaces with vacancy defects

The activation of methane on graphite surfaces with monovacancies and 5-8-5 vacancies have been investigated using density functional theory. Sixteen different initial adsorption configurations were investigated to identify the most favorable activation site. It is found that methane tends to be activated on the defective graphite surfaces, and the most stable configuration is that methane activation happened in the center hole of the monovacancy site, with a reaction energy of 1.13 eV. Electron transfer and weaker electrostatic potential of the vacancy region indicate that carbon atom of methane tends to fill the vacancy and makes the system more stable.