Morphological Investigation of Midblock‐Sulfonated Block Ionomers Prepared from Solvents Differing in Polarity

Mineart, Kenneth P.; Jiang, Xi; Jinnai, Hiroshi; Takahara, Atsushi; Spontak, Richard J.

doi:10.1002/marc.201400627

Cited by 47 publications

(74 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, the performance of OPVs can be improved through the physical incorporation of conductive nanoscale objects (e.g., carbon nanotubes) to produce hybrid materials. Since the morphologies of block ionomers can be solvent-templated [ 34 ] and to ensure that the ionic pathway in these SBIs is continuous, fi lms have been cast from a polar organic solvent. Another class of promising and inexpensive OPVs that have received substantial attention since the seminal work of Grätzel and co-workers [ 16,17 ] includes dye-sensitized solar cells (DSSCs).…”

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

“…This observation verifi es that Ru(bpy) 3 complexes with the polymer in the presence of water. [ 34 ] These channels, measuring 12-14 nm across, are the result of using a polar casting solvent. This difference is accompanied by the development of a second peak located at 1040 cm −1 and similarly suggests that Ru(bpy) 3 complexes with both the polymer and DAS.…”

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

“…This difference is accompanied by the development of a second peak located at 1040 cm −1 and similarly suggests that Ru(bpy) 3 complexes with both the polymer and DAS. [ 34,36 ] Even without the addition of a TiO 2 layer, the addition of photoactive dyes to a hydrated pentablock ionomer with a sulfonated midblock yields a competitive OPV design insofar as the ion-rich pathways are continuous, which can be nanotemplated from the casting solvent. These pathways are visible as the stained regions in the transmission electron microscopy (TEM) image provided in Figure 4 c and appear continuous despite the mixed morphology.…”

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

“…[ 34 ] These channels, measuring 12-14 nm across, are the result of using a polar casting solvent. [ 34 ] The specimens in (c) are surface-decorated with gold nanoparticles measuring ≈5 nm in diameter and appearing as small, dark specks. the inset in Figure 4 c).…”

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

See 3 more Smart Citations

Highly Flexible Aqueous Photovoltaic Elastomer Gels Derived from Sulfonated Block Ionomers

Al-Mohsin

Mineart

Spontak

2015

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

molecule absorbs a photon and becomes oxidized, electrons in the photosensitizer jump from their ground state to an excited state. These electrons, injected into the conduction band of TiO 2 nanoparticles, fl ow through a load to the anode where they are reintroduced into the cell and chemically reduce the dye so that the dye can absorb another photon and repeat the process. While liquid electrolytes yield high effi ciencies, [ 18 ] such devices suffer from solvent leakage and evaporation. [ 19 ] For this reason, DSSC research has shifted to using quasi-solid electrolytes, [ 20 ] and recent efforts have established [21][22][23] that the effi ciency and stability of DSSC devices containing electrolyte gels can exceed the performance of their liquid counterparts. Burschka et al. [ 24 ] have reported that solid-state DSSCs can achieve an effi ciency of 15% through the use of a hybrid perovskite dye.Ongoing demands to produce environment friendly, inexpensive, and reliable OPVs have likewise promoted the development of aqueous DSSCs. Using 1-methyl-3-propylimidazolium iodine with up to 10 wt% water has enabled a conversion effi ciency of up to 4.2%. [ 25 ] Combining a gel and dye with an aqueous environment has guided Velev and co-workers [ 26,27 ] to adopt a biomimetic approach by which to design OPVs on the basis of leaves. In this spirit, they have introduced the concept of hydrogel photovoltaic (HGPV) devices composed of an agarose gel containing 98 wt% water and exhibiting fi ll factor (FF) values up to 0.37 (the FF is a measure of the maximum power of a solar cell). Complementary FF values measured from biophotovoltaic HGPVs, inspired by the sequential charge-separation Z-scheme responsible for photosynthesis, have been recently reported by Schuhmann and co-workers [ 28,29 ] to range from 0.13 to 0.56. While the physical networks formed by natural gelling agents in HGPVs are stable, they are nonetheless mechanically fragile. Tough hydrogels substituted for this purpose tend to rely on chemical cross-linking and suffer from aging over time. To expand this biomimetic design with a physically cross-linkable macromolecule that exhibits excellent mechanical and stability attributes, we have chosen to fabricate HGPVs from self-organized multiblock copolymers, [ 30 ] each with a charged and thus hydrophilic midblock. These sulfonated block ionomers (SBIs), previously used in highly responsive ionic polymer-metal composites, [ 31 ] behave as thermoplastic elastomers (TPEs). For this reason and to retain consistency with the terminology we proposed earlier [ 32,33 ] for midblock-solvated TPE gels (as TPEGs), the resulting OPVs are hereafter referred to as photovoltaic elastomer gels (PVEGs).The PVEGs examined here are fabricated from poly[

show abstract

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

Section: Doi: 101002/aenm201401941mentioning

confidence: 99%

See 2 more Smart Citations

Highly Flexible Aqueous Photovoltaic Elastomer Gels Derived from Sulfonated Block Ionomers

Al-Mohsin

Mineart

Spontak

2015

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…Such favorable agreement implies that, despite being (i) constrained between lamellae (which behave as soft parallel surfaces [34]), (ii) tethered at one chain end, and (iii) surrounded by double-anchored midblocks, the interstitial micelles reported in this study form as if they were free micelles in the bulk. While bicomponent ABA triblock copolymers normally order into single morphologies, numerous experimental stud ies [35,36] have demonstrated that coexisting morphologies frequently develop during solvent casting. Recent evidence [37] acquired from melt-spun bicomponent fibers confirms that dual-mode nanostructures (e.g., tubes containing centerline micelles) can likewise form in solvent-free systems.…”

mentioning

confidence: 99%

Dual modes of self-assembly in superstrongly segregated bicomponent triblock copolymer melts

et al. 2015

Self Cite

View full text Add to dashboard Cite

While ABC triblock copolymers are known to form a plethora of dual-mode (i.e., order-on-order) nanostructures, bicomponent ABA triblock copolymers normally self-assemble into single morphologies at thermodynamic incompatibility levels up to the strong-segregation regime. In this study, we employ on-lattice Monte Carlo simulations to examine the phase behavior of molecularly asymmetric A(1)BA(2) copolymers possessing chemically identical endblocks differing significantly in length. In the limit of superstrong segregation, interstitial micelles composed of the minority A(2) endblock are observed to arrange into two-dimensional hexagonal arrays along the midplane of B-rich lamellae in compositionally symmetric (50:50 A:B) copolymers. Simulations performed here establish the coupled molecular-asymmetry and incompatibility conditions under which such micelles form, as well as the temperature dependence of their aggregation number. Beyond an optimal length of the A(2) endblock, the propensity for interstitial micelles to develop decreases, and the likelihood for colocation of both endblocks in the A(1)-rich lamellae increases. Interestingly, the strong-segregation theory of Semenov developed to explain the formation of free micelles by diblock copolymers accurately predicts the onset of interstitial micelles confined at nanoscale dimensions between parallel lamellae.

show abstract

Stretchable Cephalopod‐Inspired Multimodal Camouflage Systems

Escobar

Gorodetsky

2020

Advanced Materials

View full text Add to dashboard Cite

robotics. [9,10] More recently, the emergence of analogous platforms that dynamically modulate the propagation of IR radiation (i.e., heat) has facilitated exciting proof-of-principle demonstrations in areas such as energy conservation, [11,12] thermal management, [13,14] and IR camouflage. [15,16] Within this context, devices or systems that can potentially manipulate light across both the visible (400-740 nm) and IR (740 nm to 15 µm) spectral regions remain quite rare. To date, relatively few classes of these technologies have been reported, such as thermochromic phase-change materials, [17][18][19][20] electrochromic devices, [21][22][23] IR-reflecting platforms, [24,25] and reconfigurable soft machines [9] (see Table S1, Supporting Information), and they have featured drawbacks that include a limited degree of spectral modulation, impractical actuation requirements, poor stability to repeated actuation, slow response times, and/or complicated fabrication. [9,[17][18][19][20][21][22][23][24][25] Indeed, the engineering of devices and systems with tandem adaptive functionality across a broad spectral window (i.e., encompassing the visible, near-IR, short-wavelength IR, mid-wavelength IR, and long-wavelength IR) has proven challenging, in part because of the order of magnitude difference in the length scales associated with the propagation of visible and long-wavelength IR light. Consequently, there exists an impetus for the development of advanced multimodal camouflage platforms, which can present new scientific and technological opportunities across multiple fields.Some of the most prominent and impressive examples of soft, deformable systems that can reversibly and precisely change their appearance are found in nature-they are animals called coleoid cephalopods, [26][27][28][29][30][31][32] such as the Japetella heathi pelagic octopus (Figure 1A) [28] and the Taonius borealis glass squid ( Figure 1B). [29,30] These animals are capable of stunning feats of concealment, which include changing the transparency of their bodies by means of a sophisticated skin architecture that controls the transmission, absorption, and reflection of light ( Figure 1C). [26][27][28][29][30][31][32] In its most general form, the skin consists of multiple layers containing pigmented sizechanging organs called chromatophores, [33][34][35] typically narrowband-reflecting cells called iridophores, [36][37][38] and broadbandreflecting cells called leucophores [39][40][41] (Figure 1C). Although their precise arrangement and optical functionalities tend to Soft, mechanically deformable materials and systems that can, on demand, manipulate light propagation within both the visible and infrared (IR) regions of the electromagnetic spectrum are desirable for applications that include sensing, optoelectronics, robotics, energy conservation, and thermal management. However, the development of such technologies remains exceptionally difficult, with relatively few examples reported to date. Herein, this challenge is addressed by engineering ceph...

show abstract

Morphological Investigation of Midblock‐Sulfonated Block Ionomers Prepared from Solvents Differing in Polarity

Cited by 47 publications

References 56 publications

Highly Flexible Aqueous Photovoltaic Elastomer Gels Derived from Sulfonated Block Ionomers

Highly Flexible Aqueous Photovoltaic Elastomer Gels Derived from Sulfonated Block Ionomers

Dual modes of self-assembly in superstrongly segregated bicomponent triblock copolymer melts

Stretchable Cephalopod‐Inspired Multimodal Camouflage Systems

Contact Info

Product

Resources

About