Systematic first-principles study on the Ni and X (X = C, N, O, F, P, S, Cl, Se, and Te) codoped monolayer WS2 (W15Ni1S26X6)

Abstract The Ni and X (X = C, N, O, F, P, S, Cl, Se, and Te) codoped monolayer WS2 (W15Ni1S26X6) alloys were studied systematically by using the first-principles methods. The volume V of Ni and X codoped WS2 unit cell deceases with the deceasing atomic radius of X belonging to the same period or group in the periodic table of the elements. The codoped W15Ni1S26X6 (X = C, N, O, F, P, S, Cl, Se, and Te) alloys are easier to form under the W-rich condition than under the S-rich condition. The W15Ni1S26O6 and W15Ni1S26C6 alloys are the easiest and the hardest to form, due to the lowest and the highest formation energies, respectively. Only the HM W15Ni1S26Se6 alloy with a large magnetic moment of about 4 μ B can be used in the spintronic devices. The Ni and X (X = S, Se, F, and Cl) codoped HM W15Ni1S26X6 alloy has the superiority for the optical use compared with the pristine W16S32 alloy.