Carbon sheet fabricated by hydrothermal process

Abstract

This paper suggests new material, carbon sheet, in replacement of graphene oxide through simple and environment-friendly process. Graphene oxide-like carbon sheet is a two-dimensional structure of carbon atoms decorated with abundant oxygen functional groups on both basal planes and edges such as hydroxyl groups, epoxy groups, carbonyl groups and carboxyl group. The geometric and chemical structure of carbon sheet is verified by various characterization tools. Carbon sheet synthesis is more competitive than graphene oxide regarding mass production. The limitation of graphene oxide synthesis is longer reaction time and formation of toxic gas, exploder, heavy metal and wastewater (over 300 L for 1kg graphene oxide). In other hands, method, suggested by this paper, requires shorter reaction time and discharge no toxic compounds, but dispose only wastewater 0.4 L for 1kg carbon sheet. Also, the output and price of carbon sheet and graphene oxide compare to evaluate possibility commercializing carbon sheet. The output of carbon sheet is 0.1 ton m-3 day-1, 100 times bigger than that of graphene oxide, 1 kg m-3 day-1. The price of carbon sheet is $0.05 per gram considering with raw material used, 3000 times cheaper than commercial graphene oxide ($150 ~ $300 per gram). The simple and environment-friendly method facilitate mass production easily. Finally, the present study proves that carbon sheet gives high performance enhancing mechanical properties of polymer as much as graphene oxide. Small amount of carbon sheet can reinforce mechanical properties of polymer due to its high surface area, maximizing contact area, and oxygen functional group interacting with polymer. Although the performance of carbon sheet is lower than graphene oxide, carbon sheet would be a more effective filler in the point of mass production. Therefore, carbon sheet can be used as a commercial filler.