Multicompartment Nanostructures as Templates for Multimetallic Hybrid Materials

ABC triblock terpolymers are promising soft templates for organic/inorganic hybrids because of their ability to form nanostructures with complex shapes, multiple compartments, and precisely localized chemistry. Exemplified on multicompartment nanofibers (MCNFs) of triblock terpolymers, it is demonstrated that microdomains can be selectively loaded, thereby giving access to nanoscale multimetallic hybrid materials. MCNFs with micrometer length, homogenous diameter (90 nm), and a helix-on-cylinder morphology are formed from polystyrene-block-polybutadiene-block-poly(tert-butyl methacrylate) (PS-b-PB-b-PT). After postmodification (cross-linking/hydrolysis), selective loading with FeCl₃, PdCl₂, H₂PtCl₆, AgNO₃, CuCl₂, or ZnCl₂ leads to a variety of hybrid MCNFs analyzed by transmission electron microscopy, scanning transmission electron microscopy, electron tomography, energy-dispersive X-ray spectroscopy, and atomic force microscopy. Mild sulfonation of the PS shell to polystyrene sulfonate renders the MNCFs water-dispersible and allows the formation of mixed-bimetallic Pt/Pd/Pt@MCNFs and trimetallic Pt/Pd/Ag@MCNFs. It is demonstrated that the order of loading is key to successfully create multimetallic nanostructures. These and other structures can become useful for energy applications as well as in photo- and electrocatalysis.