Liquid-phase catalytic growth of graphene

The ability to mass produce graphenes at low cost is of paramount importance in bringing graphene-based technologies into market. Herein, we report the facile liquid-phase catalytic growth of graphene suitable for mass production. Iodine tincture was used to catalyze graphene quantum dots into graphene films at room temperature. This method has many advantages such as environment-friendliness, high yields, low cost and a wide choice of substrates. Furthermore, the bandgap of the graphene films is tunable by post-annealing. A photodetector based on the graphene films was developed, which could respond to a wide wavelength range between 365 and 1200 nm. It exhibited a detectivity and a responsivity of up to 1.1 × 1013 cm Hz1/2 W-1 and 81.3 mA W-1, respectively. Hence, graphene films demonstrated significant applications in the field of optoelectronics. Interestingly, the surface of the graphene film prepared by this method has wrinkles that can also be explored for energy storage applications.