Regulate chemical environment to control the formation of defects on Ta3N5 (110) surface: From theoretical perspectives

Highlights: • Defect properties of Ta₃N₅ (1 1 0) surface are studied using DFT method. • Defect formation energy is analyzed based upon rigorously verified chemical potential. • Mg is more easily doped on Ta₃N₅ (1 1 0) surface in nitrogen-rich condition. • Co-defects reduce the influence of single defects on Ta₃N₅ (1 1 0) surface. The defect properties of Ta₃N₅ (1 1 0) surface are studied by first-principles calculation. We focus on the formation of three typical defects, oxygen impurity, nitrogen vacancy, and magnesium impurity and further emphasize their roles on changing the electronic structure and band edge position of the surface. Our results show that Mg is more easily doped on (1 1 0) surface in nitrogen-rich condition, in which the formation of co-defects is energetically more favorable. These co-defects can reduce the influence of single defects on the electronic structure and band edge position of the (1 1 0) surface.