Hybrid Pickering emulsifiers (HYPIEs) via synergistic water/oil interfacial interactions: enhanced properties and applications

Abstract Emulsions stabilized by surface-active solid particles, known as Pickering emulsions, offer advantages over conventional emulsions, including enhanced stability, biocompatibility, and the potential recyclability of particles. These attributes underpin their growing use in cosmetics, food, catalysis, enhanced oil recovery, and pharmaceuticals. However, single-particle emulsifiers often lack the versatility required to precisely control emulsion formation, stability, and morphology. To address these limitations, hybrid Pickering emulsifiers (HYPIEs), which combine solid particles with secondary emulsifiers, have emerged as a powerful alternative. By improving interfacial wettability and adsorption, HYPIEs exhibit superior performance compared with their individual components and enable the co-adsorption of species with antagonistic properties, facilitating the design of smart emulsifying systems. This review categorizes HYPIEs based on synergistic combinations, including particle-particle (i.e. ‘hard’-‘hard’, ‘hard’-‘soft’, ‘soft’-‘soft’), particle-(bio)surfactant and particle-(bio)polymer systems. We elucidate the mechanisms underlying their enhanced interfacial behavior and highlight the diverse interfacial architectures that can be achieved. Finally, we discuss emerging applications of HYPIEs in shaping oil–water interfaces for catalysis, biomedicine, cosmetics, personal care, and food products, and outline current challenges and future perspectives, including strategies for tailoring synergistic functionalities and computational approaches for in silico HYPIE design.