The physical properties of Li-doped g-C3N4 monolayer sheet investigated by the first-principles

The geometric, electronic, optical properties, thermodynamic stability, and work function of Li-doped g-C3N4 monolayer were investigated by the first-principles calculation. It was found that the Li atoms were preferentially substituted the open-hollow sites of g-C3N4. Interestingly, the odd number of Li doped g-C3N4 showed metallic properties, while the even number of Li atoms widened the band gap of g-C3N4. The HOMO and LUMO distributions reveal that the active sites located at edge N and C atoms for both pristine and the Li-doped g-C3N4. In addition, thermodynamic analysis showed that the doped Li atoms reduced the thermodynamic stability of g-C3N4 monolayer sheets. (C) 2015 Elsevier Ltd. All rights reserved.