Highly tough cellulose/graphene composite hydrogels prepared from ionic liquids

Highly tough cellulose/graphene composite hydrogels (CGH) were successfully prepared by simply regenerating the mixture of wood pulp and reduced graphene oxide (rGO) from their ionic liquid (IL) solution using deionized water as coagulant. Nontoxic and cost-efficient Vitamin C was used as the reducing agent for preparing rGO directly in IL Significantly enhanced mechanical strength and thermal stability was observed with the CGH in comparison with pure cellulose hydrogels (CH), and the mechanical properties of CGH were related with the doping ratio of rGO. Over four times higher compressive Young's modulus was obtained with 0.5 wt% doping of graphite oxide (GO) in cellulose. This method provides a simple and green method to combine the extraordinary performances of graphene with the multifunctional properties of cellulose-based hydrogels, and thus holding great potential for future applications in the fields of biology and energy. (C) 2015 Elsevier B.V. All rights reserved.