title: N-type graphene induced by dissociative H₂ adsorption at room temperature.
abstract: Studies of the interaction between hydrogen and graphene have been increasingly required due to the indispensable modulation of the electronic structure of graphene for device applications and the possibility of using graphene as a hydrogen storage material. Here, we report on the behaviour of molecular hydrogen on graphene using the gate voltage-dependent resistance of single-, bi-, and multi-layer graphene sheets as a function of H₂ gas pressure up to 24 bar from 300 K to 345 K. Upon H₂ exposure, the charge neutrality point shifts toward the negative gate voltage region, indicating n-type doping, and distinct Raman signature changes, increases in the interlayer distance of multi-layer graphene, and a decrease in the d-spacing occur, as determined by TEM. These results demonstrate the occurrence of dissociative H₂ adsorption due to the existence of vacancy defects on graphene.
authors.affiliation: Interdisciplinary School of Green Energy, KIER-UNIST Advanced Center for Energy, Ulsan National Institute of Science and Technology-UNIST, Ulsan 689-798, Republic of Korea.
authors.forename: Byung Hoon
authors.initials: BH
authors.lastname: Kim
authors.forename: Sung Ju
authors.initials: SJ
authors.lastname: Hong
authors.forename: Seung Jae
authors.initials: SJ
authors.lastname: Baek
authors.forename: Hu Young
authors.initials: HY
authors.lastname: Jeong
authors.forename: Noejung
authors.initials: N
authors.lastname: Park
authors.forename: Muyoung
authors.initials: M
authors.lastname: Lee
authors.forename: Sang Wook
authors.initials: SW
authors.lastname: Lee
authors.forename: Min
authors.initials: M
authors.lastname: Park
authors.forename: Seung Wan
authors.initials: SW
authors.lastname: Chu
authors.forename: Hyeon Suk
authors.initials: HS
authors.lastname: Shin
authors.forename: Jeongmin
authors.initials: J
authors.lastname: Lim
authors.forename: Jeong Chul
authors.initials: JC
authors.lastname: Lee
authors.forename: Yongseok
authors.initials: Y
authors.lastname: Jun
authors.forename: Yung Woo
authors.initials: YW
authors.lastname: Park