Progress in graphene synthesis has led to increased interest in the assembly of graphene into superstructures, and to the fabrication of novel ordered materials from graphene or engineered graphenic molecular building blocks [1,2]. Graphene monolayers typically deposit flat on substrates or associate face-to-face to form horizontal stacked papers or multilayer coatings. The opposite structure, vertically aligned graphene layer arrays on substrates, are more difficult to fabricate, but are expected to show a range of unique properties and behaviors. Here we demonstrate a method for fabrication of vertically aligned graphene layer arrays (VAGLAs) by liquid-phase coating and carbonization of organic precursors that form "chromonic liquid crystals" js (CLCs). These CLCs are discotic dye molecules with hydrophobic faces and hydrophilic perimeters that assemble face-to-face into massive pi-stacks in aqueous solution. The ~ pi-stacks form supramolecular rods, which order into netnatic liquid crystal phases through self-avoidance at high concentration and deposit on surfaces to form up-standing graphene ribbon arrays after carbonization. The arrays can be aligned or further patterned within substrate using local shear forces, and have novel properties and behaviors because of the unique high-activity edge-rich surfaces (see Fig. 1). Potential applications of VAGLAs include Mgh-discharge-rate Li-ion thin film battery electrodes [3], polarizing thin films, active enhancing coatings on graphite electrodes, superhydrophilic surfaces, and nanopore membranes [4]. Here we demonstrate the synthesis of Z-directional aaaopores by high-temperature catalytic hydrogenation, in which cobalt nanoparticles tunnel vertically into and through the arrays as the particles track vertically following edge-plane surfaces.
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