title: Reduced Graphene Oxide Films with Ultrahigh Conductivity as Li-Ion Battery Current Collectors.
abstract: Solution processed, highly conductive films are extremely attractive for a range of electronic devices, especially for printed macroelectronics. For example, replacing heavy, metal-based current collectors with thin, light, flexible, and highly conductive films will further improve the energy density of such devices. Films with two-dimensional building blocks, such as graphene or reduced graphene oxide (RGO) nanosheets, are particularly promising due to their low percolation threshold with a high aspect ratio, excellent flexibility, and low cost. However, the electrical conductivity of these films is low, typically less than 1000 S/cm. In this work, we for the first time report a RGO film with an electrical conductivity of up to 3112 S/cm. We achieve high conductivity in RGO films through an electrical current-induced annealing process at high temperature of up to 2750 K in less than 1 min of anneal time. We studied in detail the unique Joule heating process at ultrahigh temperature. Through a combination of experimental and computational studies, we investigated the fundamental mechanism behind the formation of a highly conductive three-dimensional structure composed of well-connected RGO layers. The highly conductive RGO film with high direct current conductivity, low thickness (∼4 μm) and low sheet resistance (0.8 Ω/sq.) was used as a lightweight current collector in Li-ion batteries.
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Kun
authors.initials: K
authors.lastname: Fu
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Shuze
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Yiju
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Emily
authors.initials: E
authors.lastname: Hitz
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Dai
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Jiayu
authors.initials: J
authors.lastname: Wan
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Valencia A
authors.initials: VA
authors.lastname: Danner
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Teng
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Materials Science and Engineering and ‡Department of Mechanical Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Liangbing
authors.initials: L
authors.lastname: Hu
keywords: High conductivity; Li-ion batteries; current collector; high-temperature reduction; lightweight; reduced graphene oxide