Theoretical study of effect of nickel and gold impurities on electronic properties of graphene using Density functional theory

In this paper, we calculated the electronic properties of graphene in the presence and absence of the gold and nickelatoms using the density functional theory. The electronic structure, density of states, stability, band gap and spin polarization are studied. Our calculation is performed with SIESTA software. For this reason, we used local density approximation (LDA) and generalized gradient approximation (GGA) to calculate the exchange-correlation potential. The results show that the stability and spin polarization increase while the band gap decrease when the size of graphene increases. Graphene layer doesn’t have any spin polarization but in the presence of impurity, it shows the spin polarization depends on the gold and nickel impurities location. Also gold and nickel impurities defer the flatness of surface. The is hybridization between H(s) with C(p) ingraphene with impurities of gold and nickeland hybridization between Au(d) and Ni(d) with C(p) orbitals.