Fig. 5: DFT calculation of formation energies and charge density of states of N-WS₂.

a Calculated formation energies of four possible models of N-doped sites in few-layer WS₂. b TDOS and PDOS of pristine WS₂ flake (left) and N-WS₂ flake (right). The vacuum level is aligned and the Fermi level is set at 0 eV