Graphene Oxide Glue-Electrode for Fabrication of Vertical, Elastic, Conductive Columns

Graphene has a planar atomic structure with high flexibility and might be used as ultrathin conductive glues or adhesion layers in electronics and other applications. Here, we show that graphene oxide (GO) sheets condensed from solution can act as a pure, thin-layer, nonpenetrating glue for fabrication of vertical architectures anchored on rigid and flexible substrates. Carbon nanotube (CNT) sponges are used as a porous template to make polymer-reinforced composite columns, to achieve both high conductivity and elastic behavior. These vertical columns are fixed on a substrate by reduced GO sheets as an electrode and exhibit reversible resistance change under large-strain compression for many cycles. Similar to the CNT gecko feet, we disclose high adhesion forces at the CNT-GO and GO-SiO₂ interfaces by mechanical tests and theoretical calculation. Three-dimensional CNT, graphene, and nanowire networks with our GO glue-electrodes have potential applications as energy storage electrodes, flexible sensors, functional composites, and vertical interconnects.