CuCl₂-doped graphene-based screen printing conductive inks

The preparation of graphene-based conductive inks and their application in the field of flexible electronics have been extensively studied. However, improving the conductivity of the printed patterns always induces the neglect of the rheological properties of the graphene-based conductive inks or the mechanical properties of the as-printed patterns. In this study, the p-type doping of graphene with CuCl₂ as the dopant is realized through liquid phase reaction, and the doped graphene powders are used to prepare the graphene-based conductive inks with a conductivity of 3.13 × 10⁴ S m⁻¹. Subsequently, to simplify the preparation of inks, CuCl₂ is directly added into the graphene-based conductive inks, achieving the p-type doped graphene ink with the conductivity of 3.64 × 10⁴ S m⁻¹. The read range of ultrahigh-frequency radio frequency identification antenna and the temperature of the flexible electrothermal film printed with the CuCl₂-doped graphene-based conductive inks can reach 7.15 m and 200°C, respectively when the equivalent isotropically radiated power is equal to 4 W and the input power density is 0.94 W cm⁻². Moreover, good rheological properties of the conductive inks and high mechanical properties of the printed patterns are also obtained.