First-principles calculations on structural, electronic properties of V-doped 2H-NbSe2

Doping strategy has been applied in lots of areas holding promising performance for many functions. Here, we systemically report the main trends in structural, electronic properties and chemical bonding for V doped into 2H-NbSe2 in two types of doping by means of the first-principles PBE-GGA calculations. To investigate the stability of the doped system with changing concentration of V atoms, 2 × 2 × 1, 3 × 3 × 1 and 4 × 4 × 1 2H-NbSe2 supercells have been taken into consideration. Results show that it is easier to be doped as the concentration of dopant V is lower and the substituted doping structure is more stable than that of the dopant embedded into the interlayer. In addition, it is found that the dopant V atom forms a covalent bond with the surrounding Se atoms in both of the two doping structures, which can explain the variations of the structural parameters after V atom is doped into 2H-NbSe2. Moreover, what leads to the variation of the electronic structures is that the asymmetric structure and the more energetic Se atoms firstly near the dopant V atom after V is doped into 2H-NbSe2 in both of the two doping types. Our calculation results can provide good theoretical knowledge for the subsequent experiments.