Tailoring block copolymer nanoporous thin films with acetic acid as a small guest molecule

Álvarez-Fernández, Alberto; Valdes‐Vango, Fernando; Martín, José Ignacio; Vélez, María; Quirós, C.; Hermida‐Merino, Daniel; Portale, Giuseppe; Alameda, J. M.; Alonso, Francisco

doi:10.1002/pi.5901

Cited by 8 publications

(7 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Particularly, the precise control of the gold NP positions within a line/space pattern fabricated from the O 70 network (see Figure A), could find very interesting applications as a metasurface design due to the possibility of having a more precise control over the interparticle distances compared with the standard hexagonal packing. Other interesting structures, e.g., hexagonally ordered nanorings, [ 282–284 ] square, [ 285 ] or hexagonal [ 286 ] 2D Archimedean tilings patterns have been recently obtained using a linear terpolymer, supramolecular assembly, and 3‐miktoarm star copolymers (Figure 6A).…”

Section: D Gyroid Metamaterialsmentioning

confidence: 99%

Block Copolymer Directed Metamaterials and Metasurfaces for Novel Optical Devices

Álvarez-Fernández

Cummins

Saba

et al. 2021

Advanced Optical Materials

Self Cite

View full text Add to dashboard Cite

readily observed in nature, e.g., artificial magnetism, [1] negative refractive index, [2][3][4] epsilon-and-mu-near-zero, [5] light trapping, [6] or low frequency plasmons. [7] Such properties make metamaterials a promising platform to design devices with a wide range of uses for society including super-resolution imaging, [8][9][10] invisibility cloaking, [11][12][13] chemical/ biomolecular sensing, [14][15][16] antennas, [17] or absorbers. [18,19] These new functionalities can be achieved by for example using building blocks (so-called meta-atoms) arranged at length scales that are much smaller than the incident wavelength. [20][21][22] In this review article, we focus on the engineering of the optical properties for metamaterials active in the visible and near-infrared (IR) wavelength range. Structural features should be on length scales significantly smaller than the visible wavelengths (400-750 nm) to avoid

show abstract

Section: D Gyroid Metamaterialsmentioning

confidence: 99%

Block Copolymer Directed Metamaterials and Metasurfaces for Novel Optical Devices

Álvarez-Fernández

Cummins

Saba

et al. 2021

Advanced Optical Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…Traditional methods of examining nanoscale surface morphologies, such as atomic force microscopy (AFM) or scanning electron microscopy (SEM), are widely employed in the characterization of thin-film mesoporous materials. − Image analysis of top-view and cross-sectional micrographs can provide quantitative information about the open pores present on the sample. Yet, the accessible sample volume is restricted to the surface and the cleaved cross-section, raising questions of validity for the entire film.…”

Section: Introductionmentioning

confidence: 99%

Structural Characterization of Mesoporous Thin Film Architectures: A Tutorial Overview

Álvarez-Fernández

Reid

Fornerod

et al. 2020

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

Mesoporous thin film architectures are an important class of materials that exhibit unique properties, which include high surface area, versatile surface functionalization, and bicontinuous percolation paths through a broad library of pore arrangements on the 10 nm length scale. Although porosimetry of bulk materials via sorption techniques is common practice, the characterization of thin mesoporous films with small sample volumes remains a challenge. A range of techniques are geared toward providing information over pore morphology, pore size distribution, surface area and overall porosity, but none of them offers a holistic evaluation and results are at times inconsistent. In this work, we present a tutorial overview for the reliable structural characterization of mesoporous films. Three model samples with variable pore size and porosity prepared by block copolymer (BCP) coassembly serve for a rational comparison. Various techniques are assessed side-by-side, including scanning electron microscopy (SEM), atomic force microscopy (AFM), grazing incidence small-angle X-ray scattering (GISAXS), and ellipsometric porosimetry (EP). We critically discuss advantages and limitations of each technique and provide guidelines for reliable implementation.

show abstract

“…We note that out approach is fundamentally different to the more common route of pore expansion by supramolecular co-assembly with swelling agents that selectively interact with the pore-forming block, e.g. benzene derivatives, [58,59] homopolymers, [52,60] carboxylic acids, [61,62] or solvents such as toluene or xylene. [63,64] In contrast to the herein presented strategy, swelling agents present multiple challenges, i.e.…”

Section: Resultsmentioning

confidence: 98%

Fractionation of Block Copolymers for Pore Size Control and Reduced Dispersity in Mesoporous Inorganic Thin Films

Fernandez¹,

Reid²,

Suthar³

et al. 2020

Preprint

View full text Add to dashboard Cite

Mesoporous inorganic thin films are promising materials architectures for a variety of applications, including sensing, catalysis, protective coatings, energy generation and storage. In many cases, precise control over a bicontinuous porous network on the 10-nm length scale is crucial for their operation. A particularly promising route for structure formation utilizes block copolymer (BCP) micelles in solution as sacrificial structure-directing agents for the co-assembly of inorganic precursors. This method offers pore size control via the molecular weight of the pore forming block and is compatible with broad materials library. On the other hand, the molecular weight dependence impedes continuous pore tuning and the intrinsic polymer dispersity presents challenges to the pore size homogeneity. To this end, we demonstrate how chromatographic fractionation of BCPs provides a powerful method to control the pore size and dispersity of the resulting mesoporous thin films. We apply a semi-preparative size exclusion chromatographic fractionation to a polydisperse poly(isobutylene)-block-poly(ethylene oxide) (PIB-b-PEO) BCP obtained from scaled-up synthesis. The isolation of BCP fractions with distinct molecular weight and narrowed dispersity allowed us to not only tune the characteristic pore size from 9.1±1.5 to 14.1±2.1 nm with the identical BCP source material, but also significantly reduce the pore size dispersity compared to the non-fractionated BCP. Our findings offer a route to obtain a library of monodisperse BCPs from a polydisperse feedstock and provide important insights on the direct relationship between macromolecular characteristics and the resulting structure-directed mesopores, in particular related to dispersity.

show abstract

Tailoring block copolymer nanoporous thin films with acetic acid as a small guest molecule

Cited by 8 publications

References 47 publications

Block Copolymer Directed Metamaterials and Metasurfaces for Novel Optical Devices

Block Copolymer Directed Metamaterials and Metasurfaces for Novel Optical Devices

Structural Characterization of Mesoporous Thin Film Architectures: A Tutorial Overview

Fractionation of Block Copolymers for Pore Size Control and Reduced Dispersity in Mesoporous Inorganic Thin Films

Contact Info

Product

Resources

About