Study on the photoelectric and electromagnetic properties of nonmetal elements X(X=B, C, N) doping bilayer CdS

Abstract

In this paper, the electronic, magnetic and optical properties of nonmetal elements doping BL-CdS systems are calculated by DFT + U. The stable structures of nonmetal elements doping BL-CdS are obtained by calculating E_f. The analysis of electronic structures indicates that BL-CdS is semiconductor with direct band gap 2.56eV. The 2B@2S and 2C@2S systems exhibit semiconductor characteristics. B@S, C@S, N@S and 2N@2S systems present magnetic semiconductor properties and magnetism mainly comes from the spin polarization of impurity atoms. Cd atoms lose electrons, S and impurity atoms get electrons. With increase in the number of impurity atoms, number of electrons obtained is gradually increasing. The work function of BL-CdS is 6.26eV. B@S and 2C@2S have the smaller work function, indicating that two systems have higher electron mobility. The calculation of optical properties shows that BL-CdS has good photoelectric properties in visible light and the doping systems have better photoelectric properties in ultraviolet region or infrared region. ML-CdS, BL-CdS, 2B@2S systems show high performance of photocatalytic water splitting. The research results provide ideas for nano-spintronic devices and photodetectors.