Tailoring electronic properties of bilayer tri-s-triazine C3N4 using spatial modification: An ab-initio study

In the present work, change in electronic properties due to structural modification of bilayer g-C3N4 using density functional theory has been studied. We have considered shifting and rotation of one layer parallel to the second fixed layer and optimised three different arrangements. The stability of the bilayer was examined by calculating the total energy of all the structures. Specific bilayer arrangement having 180° rotation has been found most stable. The study of density of states reveals band gap of this structure to be 0.60 eV. From HOMO-LUMO and partial density of states it is seen that the stability and properties of bilayer g-C3N4 highly depends on the arrangement of N-2p and C-2p orbitals in both the layers. The inclusion of van der Waals (vdW) interaction changes the properties in z axis due to coupled orbital and columbic interaction between the layers and individual orbitals.