title: Enhanced thermopower of graphene films with oxygen plasma treatment.
abstract: In this work, we show that the maximum thermopower of few layers graphene (FLG) films could be greatly enhanced up to ∼700 μV/K after oxygen plasma treatment. The electrical conductivities of these plasma treated FLG films remain high, for example, ∼10(4) S/m, which results in power factors as high as ∼4.5 × 10(-3) W K(-2) m(-1). In comparison, the pristine FLG films show a maximum thermopower of ∼80 μV/K with an electrical conductivity of ∼5 × 10(4) S/m. The proposed mechanism is due to generation of local disordered carbon that opens the band gap. Measured thermopowers of single-layer graphene (SLG) films and reduced graphene oxide (rGO) films were in the range of -40 to 50 and -10 to 20 μV/K, respectively. However, such oxygen plasma treatment is not suitable for SLG and rGO films. The SLG films were easily destroyed during the treatment while the electrical conductivity of rGO films is too low.
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 637819, Singapore.
authors.forename: Ni
authors.initials: N
authors.lastname: Xiao
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Dong
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.forename: Dayong
authors.initials: D
authors.lastname: Liu
authors.forename: YeeYan
authors.initials: Y
authors.lastname: Tay
authors.forename: Shixin
authors.initials: S
authors.lastname: Wu
authors.forename: Lain-Jong
authors.initials: LJ
authors.lastname: Li
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Ting
authors.initials: T
authors.lastname: Yu
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Huey Hoon
authors.initials: HH
authors.lastname: Hng
authors.forename: Pulickel M
authors.initials: PM
authors.lastname: Ajayan
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Yan