Abstract
Bicontinuous jammed emulsions (or bijels) are tortuous, interconnected structures of two immiscible liquids, kinetically trapped by colloidal particles that are irreversibly bound to the oil–water interface1,2. A wealth of applications has been proposed for bijels in catalysis, energy storage and molecular encapsulation3,4,5, but large domain sizes (on the order of 5 µm or larger) and difficulty in fabrication pose major barriers to their use6,7,8. Here, we show that bijels with sub-micrometre domains can be formed via homogenization, rather than spinodal decomposition. We achieve this by using nanoparticle surfactants: polymers and nanoparticles of complementary functionality (for example, ion-pairing) that bind to one another at the oil–water interface9,10. This allows the stabilization of the bijel far from the demixing point of the liquids, with interfacial tensions on the order of 20 mN m−1. Furthermore, our strategy is extremely versatile, as solvent, nanoparticle and ligand can all be varied.