Abstract <p>A novel method has been proposed for preparing stable highly concentrated Pickering emulsions stabilized with 2D particles of carbon nitride (g-C₃N₄) and its mixtures with graphene oxide (GO) in a water/<i>n</i>-hexane system due to electrostatic interactions with zinc acetate (Zn(OAc)₂). Optical microscopy and sedimentation stability analysis have been employed to determine optimal conditions for preparing emulsions with g-C₃N₄ concentrations up to 6 mg/mL. The formation of oil-in-water (o/w) emulsions stabilized with either g-C₃N₄ particles or GO/g-C₃N₄ binary dispersions has been confirmed by fluorescence microscopy using a water-soluble dye, fluorescein. Measurements of the ζ-potentials of g-C₃N₄ sols and emulsions stabilized with g-C₃N₄ have made it possible to determine the main stabilization mechanism of the highly concentrated Pickering emulsions. It has been found that acetate ions (CH₃COO⁻) promote migration of negatively charged g-C₃N₄ particles from the aqueous phase to the interfaces, while zinc cations (Zn²⁺) are adsorbed on the g-C₃N₄ surface, thereby suppressing the mutual repulsion of the particles in the shells of emulsion droplets. During the formation of Pickering emulsions based on GO/g-C₃N₄ binary disperse systems, metal clusters contribute to the stabilization of emulsions due to coordination bonding between GO carboxyl groups and g-C₃N₄ particles. This mechanism provides efficient particle integration at the interfaces and prevents the highly concentrated Pickering emulsions from separation. The results obtained open up prospects for developing universal catalytic systems with controllable properties to be used for the degradation of organic pollutants and the synthesis of functional materials.</p>