Salting Up of Chemically Modified Graphene to Assemble Large-Scale Transparent Conductive Films

Abstract

I report a method for assembling large-scale transparent conductive films (TCFs) through the phenomenon of "salting up" of chemically modified graphene (CMG) in the presence of metallic salts. The method described herein was inspired by the well-known protein purification process, 'salting-out.' In contrast, addition of hydrophobic CMGs to the solution of a salt results in 'salting-up' of CMGs. Owing to the presence of the salt, dehydrated CMG flakes spontaneously form an extremely thin layer at the air-water interface. The salted-up CMGs spontaneously form an extremely thin layer of CMGs at air-water interface, which is a useful method to prepare a conducting film with an extremely largearea. This CMG film can be transferred to any other flexible substrate as a TCF film and be enlarged to a greater scale depending on size of air-water interface. I demonstrate a new way to fabricate TCF film that can be applied in the fabrication of large scale graphene-based electronic devices.