Decoratable hybrid-film-patch stabilized Pickering emulsions and their catalytic applications

We demonstrated a method to fabricate functional hybrid film patches that were used to form Pickering emulsions (PEs). The hybrid patches were made of carbon nanotubes, Fe₃O₄ nanoparticles, octadecyltrimethoxysilane, and poly(diallyldimethylammonium chloride). The aqueous phase of the hybrid-patch stabilized PEs can be easily separated by applying a magnetic field. The hybrid-film-patch stabilized PEs are extremely stable and lasted for eight months at room temperature. Furthermore, they are easily ruptured by adding ethanol, and regenerated by vortexing the patches in aqueous/oil mixtures, enabling the inner hydrophilic side of the patches to be easily modified with metal nanoparticles. As an example, palladium nanoparticles were embedded into the surface of the hybrid patches using an in situ reduction method. The Pd functionalized patch formed PEs showed an excellent catalytic performance for the hydrogenation of acetone with a yield of 99.5%. The same batch of Pd functionalized patches was recycled 13 times without loss of the catalytic activity. The hybrid-patch formed PEs have a great potential in the catalytic field. [Figure not available: see fulltext.]