Homogeneous bilayer graphene film based flexible transparent conductor

TL;DR

This paper demonstrates a novel bilayer graphene film grown via low pressure chemical vapor deposition as a highly efficient, uniform, and flexible transparent conductor with superior bending durability compared to traditional materials.

Contribution

It introduces the first use of bilayer graphene grown by CVD as a transparent conductor, offering improved uniformity, lower sheet resistance, and enhanced flexibility over existing multi-layer or single layer graphene.

Findings

Achieved 180 Ω/□ sheet resistance at 83% transmittance.

Bilayer graphene shows less than 15% resistance change under 2.14% strain.

Demonstrated superior bending durability compared to indium oxide films.

Abstract

Graphene is considered a promising candidate to replace conventional transparent conductors due to its low opacity, high carrier mobility and flexible structure. Multi-layer graphene or stacked single layer graphenes have been investigated in the past but both have their drawbacks. The uniformity of multi-layer graphene is still questionable, and single layer graphene stacks require many transfer processes to achieve sufficiently low sheet resistance. In this work, bilayer graphene film grown with low pressure chemical vapor deposition was used as a transparent conductor for the first time. The technique was demonstrated to be highly efficient in fabricating a conductive and uniform transparent conductor compared to multi-layer or single layer graphene. Four transfers of bilayer graphene yielded a transparent conducting film with a sheet resistance of 180 {\Omega}_{\square} at a transmittance of 83%. In addition, bilayer graphene films transferred onto plastic substrate showed remarkable robustness against bending, with sheet resistance change less than 15% at 2.14% strain, a 20-fold improvement over commercial indium oxide films.