Three defect types transformation of vertical graphene by elevating temperature

Clarifying the performance differences among sp3 hybrid, vacancy-like and boundary-like types of vertical graphene (VG) can enhance its extensive application. However, there is currently no systematic report on the reciprocal transformation of these defect types. Furthermore, it is crucial to investigate the growth characteristics of each defect type of VG and their transformation mechanisms. Herein, three defect types VG were successfully grown on copper foil by regulating the growth temperature. As the growth temperature increased, VG transitioned from sp3 hybrid type to vacancy-like type and then evolved into boundary-like type. This transformation can be primarily attributed to an increase in carbon nanosheets density at higher temperatures. Each type of VG defect offers distinct advantages for various applications: sp3 type VG exhibits excellent in-plane thermal conductivity, vacancy-like type VG shows good hydrophobicity, and boundary-like type VG has low reflectance in the near infrared region. Meanwhile, these applications are promising to redefine the defect type in the future. By analyzing the preparation and properties, this work deepen the insight to the different defect types of VG.