Pulsed-grown graphene for flexible transparent conductors

Abstract

In the race to find novel transparent conductors for next-generation optoelectronic devices, graphene is supposed to be one of the leading candidates, as it has the potential to satisfy all future requirements. However, the use of graphene as a truly transparent conductor remains a great challenge because its lowest sheet resistance demonstrated so far exceeds that of the commercially available indium tin oxide. The possible cause of low conductivity lies in its intrinsic growth process, which requires further exploration. In this work, I have approached this problem by controlling graphene nucleation during the chemical vapor deposition process as well as by adopting three distinct procedures, including bis(trifluoromethanesulfonyl)amide doping, post annealing, and flattening of graphene films. Additionally, van der Waals stacked graphene layers have been prepared to reduce the sheet resistance effectively. I have demonstrated an efficient and flexible transparent conductor with the extremely low sheet resistance of 40 Ω sq⁻¹, high transparency (T_r ∼90%), and high mechanical flexibility, making it suitable for electrode materials in future optoelectronic devices.