The electronic and optical properties of g-ZnO/Gra, doping and defective g-ZnO/Gra systems are calculated by first principles method. The Ef, Bader charge transfer and Work function are calculated. The results show that Si@Zn, P@O, Si-P@Y, VO, VZn, and VO-Zn are stable structures by calculating Ef. Si@Zn system is indirect band-gap semiconductor (0.32 eV). The dielectric function and absorption coefficient of doping and defect systems are enhanced. Absorption coefficient of VZn is the largest in visible light region. Meanwhile, the charge transfer increases in Si@Zn, Si-P@Y, VZn and VO-Zn, and Si@Zn has the largest charge transfer. The work function of Si@Zn, Si-P@Y, VO, VZn and VO-Zn systems decreases compared with g-ZnO/Gra, indicating that electrons are prone to transition in these systems. The decrease of the electrostatic potential difference in Si@Zn and Si-P@Y indicates that electrons are easily transferred. The study will provide theoretical support for the research of optoelectronic devices.

Study on the optoelectronic properties of g-ZnO/Graphene heterojunction by doping and point vacancy defects