title: Complete corrosion inhibition through graphene defect passivation.
abstract: Graphene is expected to enable superior corrosion protection due to its impermeability and chemical inertness. Previous reports, however, demonstrate limited corrosion inhibition and even corrosion enhancement of graphene on metal surfaces. To enable the reliable and complete passivation, the origin of the low inhibition efficiency of graphene was investigated. Combining electrochemical and morphological characterization techniques, nanometer-sized structural defects in chemical vapor deposition grown graphene were found to be the cause for the limited passivation effect. Extremely fast mass transport on the order of meters per second both across and parallel to graphene layers results in an inhibition efficiency of only ∼50% for Cu covered with up to three graphene layers. Through selective passivation of the defects by atomic layer deposition (ALD) an enhanced corrosion protection of more than 99% was achieved, which compares favorably with commercial corrosion protection methods.
authors.affiliation: Graduate Institute of Opto-Mechatronics, National Chung Cheng University , 168 University Road, Min-Hsiung Township, Chiayi County, Taiwan 62102.
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Hsieh
authors.forename: Mario
authors.initials: M
authors.lastname: Hofmann
authors.forename: Kai-Wen
authors.initials: KW
authors.lastname: Chang
authors.forename: Jian Gang
authors.initials: JG
authors.lastname: Jhu
authors.forename: Yuan-Yao
authors.initials: YY
authors.lastname: Li
authors.forename: Kuang Yao
authors.initials: KY
authors.lastname: Chen
authors.forename: Chang Chung
authors.initials: CC
authors.lastname: Yang
authors.forename: Wen-Sheng
authors.initials: WS
authors.lastname: Chang
authors.forename: Li-Chyong
authors.initials: LC
authors.lastname: Chen