Fabrication of graphene-like structured solid acid catalysts and their application in the saccharification of cellulose

Graphene oxide, which exhibits extraordinary acidic properties and a high theoretical surface area, is a good candidate for the catalytic transformation of biomass resources to valuable chemicals and biofuels. In this study, graphene oxide was prepared through various graphite oxide exfoliation methods, including sonication, microwave irradiation, and freeze-thaw cycling, and the activity of the prepared catalysts was evaluated in the saccharification of cellulose. The results indicated that graphene oxide prepared via these methods exhibited superior catalytic performances compared to graphite oxide; however, no significant difference in the catalytic activity of the graphene oxide catalysts was observed based on the exfoliation method used. Therefore, we proposed that thinning of graphite oxide improves its catalytic activity by increasing the contact efficiency between the substrate and the catalyst; however, this is not dependent on the exfoliation method used to prepare the graphene oxide.