title: High-quality monolayer graphene synthesis on Pd foils via the suppression of multilayer growth at grain boundaries.
abstract: The segregation of carbon from metals in which carbon is highly soluble, such as Ni (≈1.1 atom% at 1000 °C), is a typical method for graphene growth; this method differs from the surface-catalyzed growth of graphene that occurs on other metals such as Cu (<0.04 atom%). It has not been established whether strictly monolayer graphene could be synthesized through the traditional chemical vapor deposition route on metals where carbon is highly soluble, such as Pd (≈3.5 atom%). In this work, this issue is investigated by suppressing the grain boundary segregation using a pretreatment comprising the annealing of the Pd foils; this method was motivated by the fact that the typical thick growths at the grain boundaries revealed that the grain boundary functions as the main segregation channel in polycrystalline metals. To evaluate the high crystallinity of the as-grown graphene, detailed atomic-scale characterization with scanning tunneling microscopy is performed.
authors.affiliation: Center for Nanochemistry (CNC), Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, People's Republic of China.
authors.forename: Donglin
authors.initials: D
authors.lastname: Ma
authors.forename: Mengxi
authors.initials: M
authors.lastname: Liu
authors.forename: Teng
authors.initials: T
authors.lastname: Gao
authors.forename: Cong
authors.initials: C
authors.lastname: Li
authors.forename: Jingyu
authors.initials: J
authors.lastname: Sun
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Nie
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Ji
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiuju
authors.initials: X
authors.lastname: Song
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhongfan
authors.initials: Z
authors.lastname: Liu
keywords: chemical vapor deposition; graphene; palladium