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The field of quantum materials has experienced rapid growth over the past decade, driven by exciting new discoveries with immense transformative potential. Traditional synthetic methods to quantum materials have, however, limited the exploration of architectural control beyond the atomic scale. By contrast, soft matter self‐assembly can be used to tailor material structure over a large range of length scales, with a vast array of possible form factors, promising emerging quantum material properties at the mesoscale. This review explores opportunities for soft matter science to impact the synthesis of quantum materials with advanced properties. Existing work at the interface of these two fields is highlighted, and perspectives are provided on possible future directions by discussing the potential benefits and challenges which can arise from their bridging.

 

Surface segregation in blended polymer films has attracted much interest in fundamental research as well as for practical applications. A variety of methodologies have been proposed for controlling surface segregation. They often require long annealing times, however, to achieve thermodynamic equilibrium. Here, a strategy and proof‐of‐principle experiments are described to control surface segregation of thin block‐copolymer (BCP) layers on top of a homopolymer in a single casting step from blended BCP/homopolymer solutions. The surface coverage by the minor constituent BCP (2–10 wt%) is accomplished despite almost identical surface energies of BCP and homopolymer constituents. Immersing this casted solution into water for nonsolvent induced phase separation (NIPS), a nonequilibrium process, affords solidified bilayer ultrafiltration membranes composed of a thin porous surface layer of self‐assembled BCP atop an asymmetric porous homopolymer substructure. Key to successful BCP surface segregation is the choice of a binary solvent system based on careful considerations of solvent surface energies and polymer‐solvent interaction parameters. Furthermore, stabilizing the BCP micellar structure by a divalent metal additive is also essential. The approach provides a cost‐effective method for fabricating bilayer‐type asymmetric ultrafiltration membranes with uniform BCP self‐assembly based selective top surface pore layers in a single casting step.

 

Superconducting quantum metamaterials are expected to exhibit a variety of novel properties, but have been a major challenge to prepare as a result of the lack of appropriate synthetic routes to high‐quality materials. Here, the discovery of synthesis routes to block copolymer (BCP) self‐assembly‐directed niobium nitrides and carbonitrides is described. The resulting materials exhibit unusual structure retention even at temperatures as high as 1000 °C and resulting critical temperature,T_c, values comparable to their bulk analogues. Applying the concepts of soft matter self‐assembly, it is demonstrated that a series of four different BCP‐directed mesostructured superconductors are accessible from a single triblock terpolymer. Resulting materials display a mesostructure‐dependentT_cwithout substantial variation of the XRD‐measured lattice parameters. Finally, field‐dependent magnetization measurements of a sample with double‐gyroid morphology show abrupt jumps comparable in overall behavior to flux avalanches. Results suggest a fruitful convergence of soft and hard condensed matter science.

 

Nanostructured silver stands out among other plasmonic materials because its optical losses are the lowest of all metals. However, nanostructured silver rapidly degrades under ambient conditions, preventing its direct use in most plasmonic applications. Here, a facile and robust method for the preparation of highly stable nanostructured silver morphologies is introduced. 3D nanostructured gyroid networks are fabricated through electrodeposition into voided, self‐assembled triblock terpolymer scaffolds. Exposure to an argon plasma degraded the polymer and stabilized the silver nanostructure for many weeks, even in high humidity and under high‐dose UV irradiation. This stabilization protocol enables the robust manufacture of low‐loss silver nanostructures for a wide range of plasmonic applications.

 

Over the past two decades, metamaterials have led to an increasing number of biosensing and nanophotonic applications due to the possibility of a careful control of light propagating through subwavelength features. Chiral nanostructures (characterized by the absence of any mirror symmetry), in particular, give rise to unique chiro‐optical properties such as circular dichroism and optical activity. Here, a gyroid optical metamaterial with a periodicity of 65 nm exhibiting a strong circular dichroism at visible wavelengths is presented. This bottom‐up approach, based on metallic replication of the gyroid morphology in triblock terpolymer films, generates a large area of periodic optical metamaterials. A strong circular dichroism in gold and silver gyroid metamaterials at visible wavelengths is observed. It is shown that the circular dichroism is inherently linked to the handedness of the gyroid nanostructure and its tuneability is demonstrated. The optical effects are discussed and compared to other existing systems, showing the potential of bottom‐up approaches for large‐scale circular filters and chiral sensing.

 

Solid polymer electrolytes for lithium batteries promise improvements in safety and energy density if their conductivity can be increased. Nanostructured block‐copolymer electrolytes specifically have the potential to provide both good ionic conductivity and good mechanical properties. This study shows that the previously neglected nanoscale composition of the polymer electrolyte close to the electrode surface has an important effect on impedance measurements, despite its negligible extent compared to the bulk electrolyte. Using standard stainless steel blocking electrodes, the impedance of lithium salt‐doped poly(isoprene‐b‐styrene‐b‐ethylene oxide) (ISO) exhibits a marked decrease upon thermal processing of the electrolyte. In contrast, covering the electrode surface with a low molecular weight poly(ethylene oxide) (PEO) brush results in higher and more reproducible conductivity values, which are insensitive to the thermal history of the device. A qualitative model of this effect is based on the hypothesis that ISO surface reconstruction at the different electrode surfaces leads to a change in the electrostatic double layer, affecting electrochemical impedance spectroscopy measurements. As a main result, PEO‐brush modification of electrode surfaces is beneficial for the robust electrolyte performance of PEO‐containing block‐copolymers and may be crucial for their accurate characterization and use in Li‐ion batteries.

 

Rotational and oscillatory shear rheometry were used to quantify the flow behavior under minimal and significant solvent evaporation conditions for polymer solutions used to fabricate isoporous asymmetric membranes by the self‐assembly and non‐solvent induced phase separation (SNIPS) method. Three different A‐B‐C triblock terpolymer chemistries of similar molar mass were evaluated: polyisoprene‐b‐polystyrene‐b‐poly(4‐vinylpyridine) (ISV); polyisoprene‐b‐polystyrene‐b‐poly(N,N‐dimethylacrylamide) (ISD); and polyisoprene‐b‐polystyrene‐b‐poly(tert‐butyl methacrylate) (ISB). Solvent evaporation resulted in the formation of a viscoelastic film typical of asymmetric membranes. Solution viscosity and film viscoelasticity were strongly dependent on the chemical structure of the triblock terpolymer molecules. A hierarchical magnitude (ISV > ISB > ISD) was observed for both properties, with ISV solutions displaying the greatest solution viscosity, fastest film strength development, and greatest strength magnitude. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47038.

 

Mesoporous inorganic particles and hollow spheres are of increasing interest for a broad range of applications, but synthesis approaches are typically material specific, complex, or lack control over desired structures. Here it is reported how combining mesoscale block copolymer (BCP) directed inorganic materials self‐assembly and macroscale spinodal decomposition can be employed in multicomponent BCP/hydrophilic inorganic precursor blends with homopolymers to prepare mesoporous inorganic particles with controlled meso‐ and macrostructures. The homogeneous multicomponent blend solution undergoes dual phase separation upon solvent evaporation. Microphase‐separated (BCP/inorganic precursor)‐domains are confined within the macrophase‐separated majority homopolymer matrix, being self‐organized toward particle shapes that minimize the total interfacial area/energy. The pore orientation and particle shape (solid spheres, oblate ellipsoids, hollow spheres) are tailored by changing the kind of homopolymer matrix and associated enthalpic interactions. Furthermore, the sizes of particle and hollow inner cavity are tailored by changing the relative amount of homopolymer matrix and the rates of solvent evaporation. Pyrolysis yields discrete mesoporous inorganic particles and hollow spheres. The present approach enables a high degree of control over pore structure, orientation, and size (15–44 nm), particle shape, particle size (0.6–3 µm), inner cavity size (120–700 nm), and chemical composition (e.g., aluminosilicates, carbon, and metal oxides).

 

Porous polymer-derived membranes are useful for applications ranging from filtration and separation technologies to energy storage and conversion. Combining block copolymer (BCP) self-assembly with the industrially scalable, non-equilibrium phase inversion technique (SNIPS) yields membranes comprising periodically ordered top surface structures supported by asymmetric, hierarchical substructures that together overcome performance tradeoffs typically faced by materials derived from equilibrium approaches. This review first reports on recent advances in understanding the top surface structural evolution of a model SNIPS-derived system during standard membrane formation. Subsequently, the application of SNIPS to multicomponent systems is described, enabling pore size modulation, chemical modification, and transformation to non-polymeric materials classes without compromising the structural features that define SNIPS membranes. Perspectives on future directions of both single-component and multicomponent membrane materials are provided. This points to a rich and fertile ground for the study of fundamental as well as applied problems using non-equilibrium-derived asymmetric porous materials with tunable chemistry, composition, and structure.