Versatile Triblock Janus Nanoparticles: Synthesis and Self-Assembly

Multiblock Janus nanoparticles (JNPs) are anisotropic particles composed of different blocks/lobes with distinct physicochemical properties. The ultimate goal is to obtain JNPs that carry two or more contrasting bulk and surface properties on different parts of the same particle. JNPs are promising candidates for various applications, such as building blocks for self-assembly and multifunctional materials. Here, we report the chemical synthesis of a special type of "versatile" triblock JNPs, which contain three lobes with different chemical compositions, whereby "versatile" means that the triblock JNPs can be separately and independently modified on at least two different lobes through different chemical reactions, offering limitless design possibilities. We further prove that specific chemical tailoring determines the way the JNPs interact and self-assemble, such that either normal or reverse micelles are obtained. In particular, the formation of micelles from triblock JNPs constitutes an initial example of the classical concepts extension from triblock polymers to colloids. We regard the triblock JNPs as representatives of a broader class of versatile anisotropic colloids, giving the ability to combine various functionalities on different parts of the same particle, thus enriching the tool box of nanomaterials and broadening their application potential.