Transfer Medium Design for Fabrication of Graphene Barrier Films

However, the lack of reliable transfer and fabrication methods that suppress the formation of transfer-induced cracks and interlayer transport of water molecules in stacked graphene films severely limits the barrier performance of current graphene-based barrier films.

In this work, we employed a dopant-incorporated polyvinylidene difluoride with a concentration gradient as a transfer medium to suppress crack formation during transfer through conformal graphene–polymer contact and to dope graphene, thereby hindering water diffusion through enhanced water–graphene interactions. Consequently, the as-fabricated barrier film achieved an ultralow water vapor transmission rate value of 9.3 × 10^–5 g m^–2 day^–1.