Molecular amphiphiles (lipids, amphiphilic block copolymers (BCPs)) can self-assemble into a rich variety of well-defined nanostructures such as spherical micelles, cylindrical micelles, and vesicular micelles. Similar to molecular amphiphiles, inorganic nanoparticle (NP) amphiphiles, created by BCPs onto the surfaces of NPs, are representative metal-like NPs. Recently NP amphiphiles (NPAs) have become an interesting research area, because they have the unique shapes, dimensions, and intrinsic optical, electronic, and magnetic properties that are unattainable by molecular amphiphiles. The controlled assembly of NPAs enables us to tune the collective properties of NP ensembles, thus facilitating their applications in biosensing, biomedical imaging and delivery, optoelectronics, and energy production and storage. The key to fully realize the potential of these materials is to design materials with increased complexity and functionalities. A promising approach to prepare such hybrid materials is simultaneous self-assembly of multiple types of amphiphiles. However, to date, it still remains a grand challenge in achieving controllable concurrent self-assembly of molecular and colloidal amphiphiles into discrete structures. .Here we report a study on the self-assembly of binary BCPs and NPAs into polymer/inorganic nanoparticle hybrid vesicles with various morphologies by entropy-driven lateral phase separation within multi-component membranes. The morphologies include patchy vesicles with multiple small NPA domains surrounded by free BCP phase, Janus vesicles with distinguished NPA and polymer halves, and heterogeneous vesicles with uniform distribution of NPAs. The different morphologies arise from the delicate interplay between the mismatch of the chain length of the two amphiphiles, the entanglement of polymer chains, and the diffusion rate of NPAMs. Remarkably, this strategy allows the preparation of hybrid Janus vesicles with intriguing non-spherical shapes. The ability to directly integrate multiple amphiphiles with significantly different compositions, geometries, and dimensions in discrete assemblies opens new avenues to the fabrication of structurally complex hybrid materials with entirely new properties.

Entropy-driven pattern formation of hybrid vesicular assemblies of binary molecular and nanoparticle amphiphiles

247th National Meeting (2014)

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