Gyroid Nickel Nanostructures from Diblock Copolymer Supramolecules

Abstract

Nanoporous metal foams possess a unique combination of properties -they are catalytically active, thermally and electrically conductive, and furthermore, have high porosity, high surface-to-volume and strength-to-weight ratio. Unfortunately, common approaches for preparation of metallic nanostructures render materials with highly disordered architecture, which might have an adverse effect on their mechanical properties. Block copolymers have the ability to self-assemble into ordered nanostructures and can be applied as templates for the preparation of wellordered metal nanofoams. Here we describe the application of a block copolymer-based supramolecular complex -polystyrene-block-poly(4-vinylpyridine)(pentadecylphenol) PS-b-P4VP(PDP) -as a precursor for well-ordered nickel nanofoam. The supramolecular complexes exhibit a phase behavior similar to conventional block copolymers and can self-assemble into the bicontinuous gyroid morphology with two PS networks placed in a P4VP(PDP) matrix. PDP can be dissolved in ethanol leading to the formation of a porous structure that can be backfilled with metal. Using electroless plating technique, nickel can be inserted into the template's channels. Finally, the remaining polymer can be removed via pyrolysis from the polymer/inorganic nanohybrid resulting in nanoporous nickel foam with inverse gyroid morphology. Video LinkThe video component of this article can be found at

Highly Ordered Structure Formation in RAFT-Synthesized PtBOS-b-P4VP Diblock Copolymers

“…The synthesis of block copolymers and their ability to form a variety of nanoscale structures via self‐assembly has been the subject of extensive research . The structures formed depend on the degree of polymerization, , the block volume fractions, , and the interaction parameter, .For linear diblock copolymers the self‐assembled structures include spherical, cylindrical, lamellar, and bicontinuous gyroid morphologies . The latter appears in a relatively small range of the copolymer composition in the diblock copolymer phase diagram, mostly in the weak segregation regime (10 < < 40) …”

Self-assembly of hydrogen-bonded comb copolymer complexes of poly( p -hydroxystyrene) and 4-alkylpyridine amphiphiles

“…This concept has been extensively pursued by Stamm and co-workers using PS-b-P4VP diblock copolymers in combination with 2-(4-hydroxybenzeneazo)benzoic acid to create nanoporous thin films [13,14]. We studied other hydrogen bond accepting polymers besides P4VP as well [17] and used PDP-based supramolecular block copolymer bulk samples exhibiting a largelength-scale bicontinuous gyroid morphology [21] to create continuous nanoporous polymeric structures, which were used as templates to produce, e.g., metallic nickel nanofoams [16,20,46].…”

Fabrication of Small Pore-Size Nickel Foams Using Electroless Plating of Solid-State Foamed Immiscible Polymer Blends

“…Zhang et al [19] used electroplating to fabricate thin layer nickel foams with an average pore size of a ' [20] proposed a method to fabdcate nanoporous gyroidal nickel foams from block copolymer templates having a pore size of sub 50 nm. The highest porosity achieved using this method was 60%.…”