Amphiphilicity evolution in self-assembled carbon-based nanostructures for stabilizing different types of Pickering emulsions

Carbon-based nanostructures have been firmly established as highly scalable and versatile platforms, which have found extensive applications in several fields of multifunctional nanocomposites, energy storage, environment protection, and electronics device. Pickering emulsion template method is one of the efficient strategies for assembling metastable carbon nanomaterials into stable macroarchitectures. Here, the combination of graphene oxide (GO) and carbon nanotubes (CNTs) was chemically and continuously treated with 2-ethyl-4-methylimidazole (EMI) to acquire tunable wettability. The hybridization of CNTs and reduction of GO can make the as-synthesized carbon nanohybrids be capable of stabilizing oil-in-water (O/W) and water-in-oil (W/O) Pickering emulsions, respectively. The major shift in the type of Pickering emulsion is conveniently implemented through the catalytic reduction of GO by EMI. The sp2-hybridized carbon networks self-assembled with CNTs and reduced graphene oxide (RGO) are intentionally located at the biphasic liquid interface of different types of Pickering emulsions, which can endow the architecture elaborated from Pickering emulsion strategy with multiple functionalities.