title: Exceptionally strong and robust millimeter-scale graphene-alumina composite membranes.
abstract: Graphene has attracted attention as a potential strengthening material and functional component in suspended membranes as utilized in micro and nanosystems. Development of a practical and scalable fabrication process is a necessary step to allow the exceptional material properties of graphene to be fully exploited in composite structures. Using standard and scalable microfabrication processes, we fabricated free-standing chemical vapor deposition monolayer graphene-reinforced Al2O3 composite membranes, 0.5 mm in diameter, that are strong and robust. Bulge tests revealed that the graphene reinforcement increased the membrane fracture strength by a factor of at least three and maximum sustainable strain from 0.28% to at least 0.69%. We show that the graphene-reinforced membranes are even tolerant to significant cracking without loss of membrane integrity. The graphene composite membranes' freestanding area of ∼ 200 000 μm(2) is almost a thousand times larger than suspended graphene membranes reported elsewhere. The presented graphene composite membranes may be seen as representing an interesting new class of durable composite materials warranting further study and having potential for broad applicability in a variety of fields.
authors.affiliation: Department of Materials Science and Engineering, School of Chemical Technology, Aalto University, PO Box 16200, FI-00076, Finland.
authors.forename: Maria
authors.initials: M
authors.lastname: Berdova
authors.forename: Alexander Pyymaki
authors.initials: AP
authors.lastname: Perros
authors.forename: Wonjae
authors.initials: W
authors.lastname: Kim
authors.forename: Juha
authors.initials: J
authors.lastname: Riikonen
authors.forename: Tuomo
authors.initials: T
authors.lastname: Ylitalo
authors.forename: Jouni
authors.initials: J
authors.lastname: Heino
authors.forename: Changfeng
authors.initials: C
authors.lastname: Li
authors.forename: Ivan
authors.initials: I
authors.lastname: Kassamakov
authors.forename: Edward
authors.initials: E
authors.lastname: Hæggström
authors.forename: Harri
authors.initials: H
authors.lastname: Lipsanen
authors.forename: Sami
authors.initials: S
authors.lastname: Franssila