Dual-templating strategy for the fabrication of graphene oxide, reduced graphene oxide and composite scaffolds with hierarchical architectures

Abstract

The broad applications of graphene-based scaffolds demand fabrication methods that are simple and yet can create complex architectures. This is particularly true for bone tissue engineering, where interconnected, micro and macro porosity is required for cell penetration and nutrient exchange. Here, a dual-templating method is developed to produce graphene oxide (GO) scaffolds with interconnected hierarchical porosity: upon freezing and drying high internal phase emulsions exclusively stabilized by GO sheets, large pores are templated by the oil droplets, and small pores by ice crystals formed in the water phase, whose size can be controlled by freezing temperature. The resulting scaffolds are excellent substrates for mesenchymal stem cell penetration and growth. This method also enables the synthesis of complex hierarchical architectures in reduced graphene oxide (rGO) and GO composite scaffolds, through a single, versatile strategy.