Nanostructured Domains Research Articles

Tough polyamidoxime-nanocellulose supramolecular composite hydrogels for effective uranium extraction from seawater

It is highly desirable to synthesize high-performance composite hydrogels in a simple and economical manner for uranium extraction from seawater. In this study, tough polyamidoxime-nanocellulose (PAO-CNF) composite hydrogels are fabricated via supramolecular complexation. The nanostructured PAO domains are dispersed in the supramolecularly cross-linked CNF network, guaranteeing superior mechanical strength and satisfied uranium uptake in seawater. A high tensile strength of 4.3 MPa is retained for the composite hydrogels after immersion in seawater for 30 days, which is beneficial for long-term survival in the ocean. The uranium uptake capacity reaches 6.6 mg-U/g in seawater after 35-day adsorption, a synergistic effect from nanostructured PAO domains and hydrophilic CNF network. The tough supramolecular composite hydrogels have great potentials for uranium extraction from seawater, enabling sustainable development of energy and environment.

Photon-Momentum-Enabled Electronic Raman Scattering in Silicon Glass.

The nature of enhanced photoemission in disordered and amorphous solids is an intriguing question. A point in case is light emission in porous and nanostructured silicon, a phenomenon that is still not fully understood. In this work, we study structural photoemission in heterogeneous cross-linked silicon glass, a material that represents an intermediate state between the amorphous and crystalline phases, characterized by a narrow distribution of structure sizes. This model system shows a clear dependence of photoemission on size and disorder across a broad range of energies. While phonon-assisted indirect optical transitions are insufficient to describe observable emissions, our experiments suggest these can be understood through electronic Raman scattering instead. This phenomenon, which is not commonly observed in crystalline semiconductors, is driven by structural disorder. We attribute photoemission in this disordered system to the presence of an excess electron density of states within the forbidden gap (Urbach bridge) where electrons occupy trapped states. Transitions from gap states to the conduction band are facilitated through electron-photon momentum matching, which resembles Compton scattering but is observed for visible light and driven by the enhanced momentum of a photon confined within the nanostructured domains. We interpret the light emission in structured silicon glass as resulting from electronic Raman scattering. These findings emphasize the role of photon momentum in the optical response of solids that display disorder on the nanoscale.

Engineering large nanoporous networks with size and shape selected by appropriate precursors

Large domains of two-dimensional supramolecular porous nanostructures are interesting for various applications from electronics to biology. Here, we investigate the formation of Cu-coordinated networks on Cu(111) using scanning tunneling microscopy and density functional theory (DFT). We consider two molecules with three pyridyl end groups connected to a central benzene ring by either one or two phenyl groups, namely 1,3,5-tris[4-(pyridin)phenyl]benzene (TPyPB) and 1,3,5-tris[4-(pyridin)-[1,1’-biphenyl]benzene (TPyPPB), respectively. Upon deposition of TPyPB at room temperature, a honeycomb nanostructure forms, which is stabilized by Cu adatoms, as previously seen. Upon deposition at 400 K, the growth dynamics change, and molecules become trapped in the hexagonal pores. In contrast, deposition of TPyPPB at room temperature leads to vitreous structures, which rearrange at 400 K forming a low-defect and extended ordered honeycomb phase, which is also stabilized only in the presence of Cu adatoms. The DFT calculations for both honeycomb phases show an impressive agreement with the experimental results, considering the size of such structures. After annealing at 420 K, a complex flower-like structure composed of a mix of two- and three-fold coordinated Cu centers emerges. Further annealing to above 420 K leads to another new phase composed of a high molecular density motif, the so-called diamond phase.

The tellurium-induced CoSe polyhedral porous nano-structured materials as high-performance cathodes for rechargeable magnesium batteries

Rechargeable magnesium batteries (RMBs) are cost-effective and dendrite-free, making them desirable for large-scale applications. Nevertheless, the exploration of high-performance cathodes still remains a great challenge in magnesium battery research. Herein, the CoSe porous polyhedra induced by Te heteroatoms (CoSe/Te) are successfully prepared by two-step metal-organic framework (MOF)-template assisted method and investigated as high-efficiency cathodes for rechargeable MIBs. In this regard, the affluent porous structure can facilitate the transport of Mg2+ ions while the introduction of Te heteroatoms can reduce the conversion reaction barrier, boost the kinetics and redox reversibility and excite the electron conduction to build active nanostructured domains for highly reversible Mg storage reactions. As a consequence, the CoSe/Te maintains the high specific capacity of 150.6 mAh g−1 after 600 cycles at 200 mA g−1, with a superior capacity retention rate of 75.3%. Moreover, the specific capacity of such electrode materials changed from 260 mAh g−1 to 41 mAh g−1 when the current density increased from 100 mA g−1 to 2000 mA g−1, and gradually recovered to 256.5 mAh g−1 when the current density returned to 100 mAh g−1, exhibiting a better rate performance. This work highlights how micro-nanostructures can favor magnesium storage reaction reversibility and cyclability and also provide insights into rational electrode design for storing magnesium cations in future studies.

Gamma prime precipitation in as-deposited Ni-based superalloy IN713LC

The as-deposited microstructure of an additively manufactured Ni-based superalloy fabricated using laser powder-bed-fusion has been investigated using atomic resolution transmission electron microscopy. It is shown that γ′ precipitates exist in the as-deposited condition, albeit in a non-equilibrium state. The precipitates are present as nano-structured domains throughout the microstructure. These domains exhibit clear L12 ordering but show highly irregular matrix-precipitate interfaces.

Predictive combining multiple variously hybridized low-dimensional nanocarbons in a single additive for nano-sized energetic materials performance enhancement

We propose to uncover new opportunities for predictive nano-sized energetic materials performance enhancement through manipulating by vibrational interactions, energy exchange as well as heat transfer enhancement within the reaction zones at nanoscale. The combination of multiple carbon nanostructured materials with various hybridizations within a single substance can uncover new unique properties. Due to a recent fundamental discovery the collective atomic vibrations, called phonon waves, manifested in transition domains of multilayer nanostructures, incorporation of self-organized arrays of metastable nanostructures are capable controlling vibrational interactions and energy exchange within the reaction zones at nanoscale. For using this phenomenon, we propose predictive incorporation into the nano-sized energetic material composition of various carbon-based allotropes, used as catalytic nano-additives, combined with assembling them by the self-organized arrays of differently hybridized low-dimensional nanocarbon promoters. For predictive combining of multiple differently hybridized nanocarbons within a single substance we propose to use the energy-driven initiation of the allotropic phase transformations in nanocarbon promoters by concurrent electron and ion irradiation. For fine tuning the collective atomic vibrations, nanoarchitecture and functionality of the mentioned arrays of differently hybridized nanocarbon promoters we propose using combination of a set of techniques: concurrent electron and ion irradiation, using the surface acoustic waves combined with heteroatom doping along with application external electromagnetic fields and using the data-driven nanoscale manufacturing approach.

Microstructural evolution and oxidation in α/β titanium alloy under fretting fatigue loading

Coupling effects of fretting wear and cyclic stress could result in significant fatigue strength degradation, thus potentially causing unanticipated catastrophic fractures. The underlying mechanism of microstructural evolutions caused by fretting wear is ambiguous, which obstructs the understanding of fretting fatigue issues, and is unable to guarantee the reliability of structures for long-term operation. Here, fretting wear studies were performed to understand the microstructural evolution and oxidation behavior of an α/β titanium alloy up to 108 cycles. Contact surface degradation is mainly caused by surface oxidation and the generation of wear debris during fretting wear within the slip zone. The grain size in the topmost nanostructured layer could be refined to ∼40 nm. The grain refinement process involves the initial grain rotation, the formation of low angle grain boundary (LAGB; 2°–5°), the in-situ increments of the misorientation angle, and the final subdivision, which have been unraveled to feature the evolution in dislocation morphologies from slip lines to tangles and arrays. The formation of hetero microstructures regarding the nonequilibrium high angle grain boundary (HAGB) and dislocation arrays gives rise to more oxygen diffusion pathways in the topmost nanostructured layer, thus resulting in the formation of cracking interface to separate the oxidation zone and the adjoining nanostructured domain driven by tribological fatigue stress. Eventually, it facilitates surface degradation and the formation of catastrophic fractures.

Thermal Stability and Utilization of 1D-Nanostructured Co3O4 Rods Derived by Simple Solvothermal Processing

For p-type semiconductor nanoparticles, such as the cobalt oxide spinel, enhancing the nanoparticle geometry can expose more of the surface and bring up the sensitivity and applicability, pointing to even more advantageous behaviour in comparison to n-type semiconductors which are known for a somewhat faster reactivity. Here, we present a strategy that relies on fostering a simple synthetic route that can deliver reasonably or comparably performing p-type-semiconducting partially 1D-Co3O4 material prepared under less technically and economically demanding conditions. Structurally monophasic Co3O4 nanoparticles with a spinel structure were indicated by powder X-ray diffraction, while the presence of traces of organic-phase residuals in otherwise chemically homogeneous material was observed by Fourier-transform infrared spectroscopy. Scanning electron microscopy further showed that the observed fine nanoparticle matter formed agglomerates with the possible presence of rod-like formations. Interestingly, using transmission electron microscopy, it was possible to reveal that the agglomerates of the fine nanoparticulated material were actually nanostructured, i.e., the presence of 1D-shaped Co3O4 rods embedded in fine nanoparticulated matrix was confirmed. In conjunction with the N2 adsorption–desorption isotherms, discussion about the orientation, exposure of nanostructured rod domains, and derivative geometry parameters was possible. The nanostructured Co3O4 material was shown to be stable up to 800 °C whereat the decomposition to CoO takes place. The specific surface area of the nanostructured sample was raised. For the purpose of testing the photoactivity of the prepared samples, simple sorption/photodegradation tests using methylene blue as the model pollutant were performed. The degradation performance of the prepared nanostructured Co3O4 was better described by a pseudo-second-order fit, suggesting that the prepared material is worth further development toward improved and stable immobilized photocatalysts.

Xenon and Krypton Dissolved in Water Form Nanoblobs: No Evidence for Nanobubbles.

We demonstrate, experimentally and by molecular dynamics simulations, that krypton and xenon form nanostructured water-gas domains. High pressure was applied to force the inert gases to dissolve in water following Henry's law, then the liquid was depressurized, centrifuged, and inspected by dynamic light scattering. The observed objects have similar sizes and electrical properties to nanobubbles, but we found that they have fairly neutral buoyancy even at high gravitational fields. We posit that the formed nano objects are not bubbles but blobs, unique structures conceived as clathrate-hydrate precursors, thus resolving the so-called Laplace pressure bubble catastrophe.

Influence of CNT Length on Dispersion, Localization, and Electrical Percolation in a Styrene-Butadiene-Based Star Block Copolymer.

This study followed the approach of dispersing and localizing carbon nanotubes (CNTs) in nanostructured domains of block copolymers (BCPs) by shortening the CNTs via ball milling. The aim was to selectively tune the electrical and mechanical properties of the resulting nanocomposites, e.g., for use as sensor materials. Multiwalled carbon nanotubes (MWCNTs) were ground into different size fractions. The MWCNT length distribution was evaluated via transmission electron microscopy and dynamic light scattering. The nanostructure of the BCPs and the glass transition temperatures of the PB-rich and PS phases were not strongly affected by the addition of CNTs up to 2 wt%. However, AFM and TEM investigations indicated a partial localization of the shortened CNTs in the soft PB-rich phase or at the interface of the PB-rich and PS phase, respectively. The stress-strain behavior of the solution-mixed composites differed little from the mechanical property profile of the neat BCP and was largely independent of CNT amount and CNT size fraction. Significant changes could only be observed for Young’s modulus and strain at break and may be attributed to CNT localization and small changes in morphology. For nanocomposites with unmilled CNTs, the electrical percolation threshold was less than 0.1 wt%. As the CNTs were shortened, the resistivity increased and the percolation threshold shifted to higher CNT contents. Composites with CNTs ground for 7.5 h and 13.5 h showed no bulk conductivity but significantly decreased surface resistivity on the bottom side of the films, which could be attributed to a sedimentation process of the grind and thereby highly compressed CNT agglomerates during evaporation.

Immunological response of polysaccharide nanogel-incorporating PEG hydrogels in an in vivo diabetic model

Cell-based therapies hold significant advantages in comparison with the traditional drug-based or injection-based treatments. However, for long-term functional cellular implants, immune acceptance must be established. To accomplish the acceptance of the implanted cells, various biomaterial systems have been studied. Nanogels have shown great potential for modulation of cellular microenvironments, acting as a physical barrier between the immune system and the implant. However, internalization of nano-scale materials by implanted cells is not desirable and is yet to be overcome. In this study, we incorporated acrylate modified cholesterol-bearing pullulan (CHPOA) nanogels into poly (ethylene glycol) diacrylate (PEGDA) hydrogels through covalent crosslinking, where we used visible light-induced photopolymerization. We characterized morphology and swelling properties of CHPOA incorporated PEG composite hydrogels using FE-SEM and gravimetric analysis. Also, we investigated the biocompatibility properties of composite hydrogels in vivo, where we used both healthy and diabetic mice. We induced diabetes in mice using a low dose streptozotocin (STZ) injections and implanted composite hydrogels in both diabetic and healthy mice through subcutaneous route. Immune cell infiltration of the retrieved tissue was examined through histological analysis, where we observed minimum immune response levels of 0–2 rareness, according to ISO standard of biological evaluation of medical devices. Our observation suggests that the composite hydrogel developed here can be used to introduce nanostructured domains into bulk hydrogels and that this system has potential to be used as immunologically acceptable composite material in cellular therapy without internalization of nanoparticles.

Characterization and modeling of the temperature-dependent thermal conductivity in sintered porous silicon-aluminum nanomaterials

Nanostructured silicon and silicon-aluminum compounds are synthesized by a novel synthesis strategy based on spark plasma sintering (SPS) of silicon nanopowder, mesoporous silicon (pSi), and aluminum nanopowder. The interplay of metal-assisted crystallization and inherent porosity is exploited to largely suppress thermal conductivity. Morphology and temperature-dependent thermal conductivity studies allow us to elucidate the impact of porosity and nanostructure on the macroscopic heat transport. Analytic electron microscopy along with quantitative image analysis is applied to characterize the sample morphology in terms of domain size and interpore distance distributions. We demonstrate that nanostructured domains and high porosity can be maintained in densified mesoporous silicon samples. In contrast, strong grain growth is observed for sintered nanopowders under similar sintering conditions. We observe that aluminum agglomerations induce local grain growth, while aluminum diffusion is observed in porous silicon and dispersed nanoparticles. A detailed analysis of the measured thermal conductivity between 300 and 773 K allows us to distinguish the effect of reduced thermal conductivity caused by porosity from the reduction induced by phonon scattering at nanosized domains. With a modified Landauer/Lundstrom approach the relative thermal conductivity and the scattering length are extracted. The relative thermal conductivity confirms the applicability of Kirkpatrick’s effective medium theory. The extracted scattering lengths are in excellent agreement with the harmonic mean of log-normal distributed domain sizes and the interpore distances combined by Matthiessen’s rule.

Methanetriyl-pi hydrogen bonding in nonpolar domains of supramolecular nanostructures: An efficient mechanism for extraction of carcinogenic polycyclic aromatic hydrocarbons from soils

Methanetriyl-pi hydrogen bonding (CH-π HB) in nonpolar domains of supramolecular nanostructures is proposed here as a new mechanism to increase the extraction efficiency of aromatic compounds. The approach is illustrated by the extraction of priority carcinogenic polycyclic aromatic hydrocarbons (CPAHs) in soils using supramolecular nanostructures of carboxylic acids with nonpolar domains consisting of hydrocarbon chains (C6-C10) dispersed in tetrahydrofuran (THF). The high concentration of CH-groups available in the supramolecular nanostructures (38.7–47.3 M) enabled the efficient extraction of CPAHs (recoveries between 89 and 106%), using a supramolecular solvent (SUPRAS) volume/soil amount ratio of 1.5 µL mg−1 and a simple and quick procedure (stirring for 15 min and centrifugation for 10 min). SUPRAS extracts were directly analysed by liquid chromatography-fluorimetry (LC-FL). No sample clean-up or solvent evaporation was required. Optimization of the composition of the nonpolar domains of the SUPRASs was carried out varying the length and concentration of the hydrocarbon chain of the carboxylic acid and the concentration of THF. Method detection limits were in the interval 0.07–0.4 µg kg−1. The relative standard deviations (n = 18, CPAH concentration = 300 µg kg−1), obtained under repeatability and reproducibility conditions, varied within the ranges 2.8–5.4% and 4.3–8.8%, respectively. The accuracy of the method was proved by analysing a certified reference material (CRM) from an industrial soil, contaminated with priority CPAHs at concentrations at the mg kg−1 level (BAM-U013c). The concentration of CPAHs found in soils taken in Southern Spain varied in the range 0.51–49 µg kg−1. The results here obtained demonstrate that CH-π HB is a valuable mechanism for increasing the extraction of aromatic compounds from soils.

Nanoscale domains in K0.48Na0.52Nb0.96Sb0.04O3 – Bi0.5Na0.5ZrO3 ceramics enhance piezoelectric properties

(1-x) K0.48Na0.52Nb0.96Sb0.04O3 - x Bi0.5Na0.5ZrO3 [(1-x) KNNS - x BNZ] lead-free piezoelectric ceramics with R(rhombohedral)-T(tetragonal) phase boundary have been successfully synthesized. The influences of Bi0.5Na0.5ZrO3 (BNZ) doping on the phase structure, microstructure as well as dielectric properties, piezoelectric properties of the ceramics were systematically studied. It was observed by XRD and εr-T curve that the R and T phases coexisted in the ceramic samples in the range of 0.03 ≤ x ≤ 0.04. The introduction of BNZ can obviously refine the ceramic grains and improve the density of the ceramics through the observation of the SEM images. In addition, some small nanostructured domains were found in the (1-x) KNNS - x BNZ ceramic when x = 0.03, which can be attributed to the fact that the domain wall energy of the ceramics is in a low state in the R-T phase boundary region, and the optimal values of εr = 5609, tanδ = 0.035, and d33 = 278 pC/N were obtained simultaneously. Therefore, we believe that the (1-x) KNNS - x BNZ ceramics can provide a better solution for the application of lead-free piezoelectric ceramics.

Evaluation on the Intrinsic Physicoelectrochemical Attributes and Engineering of Micro-, Nano-, and 2D-Structured Allotropic Carbon-Based Papers for Flexible Electronics.

Flexible electronics have gained more attention for emerging electronic devices such as sensors, biosensors, and batteries with advantageous properties including being thin, lightweight, flexible, and low-cost. The development of various forms of allotropic carbon papers provided a new dry-manufacturing route for the fabrication of flexible and wearable electronics, while the electrochemical performance and the bending stability are largely influenced by the bulk morphology and the micro-/nanostructured domains of the carbon papers. Here, we evaluate systematically the intrinsic physicoelectrochemical properties of allotropic carbon-based conducting papers as flexible electrodes including carbon-nanotubes-paper (CNTs-paper), graphene-paper (GR-paper), and carbon-fiber-paper (CF-paper), followed by functionalization of the allotropic carbon papers for the fabrication of flexible electrodes. The morphology, chemical structure, and defects originating from the allotropic nanostructured carbon materials were characterized by scanning electron microscopy (SEM) and Raman spectroscopy, followed by evaluating the electrochemical performance of the corresponding flexible electrodes by cyclic voltammetry and electrochemical impedance spectroscopy. The electron-transfer rate constants of the CNTs-paper and GR-paper electrodes were ∼14 times higher compared with the CF-paper electrode. The CNTs-paper and GR-paper electrodes composed of nanostructured carbon showed significantly higher bending stabilities of 5.61 and 4.96 times compared with the CF-paper. The carbon-paper flexible electrodes were further functionalized with an inorganic catalyst, Prussian blue (PB), forming the PB-carbon-paper catalytic electrode and an organic conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), forming the PEDOT-carbon-paper capacitive electrode. The intrinsic attribute of different allotropic carbon electrodes affects the deposition of PB and PEDOT, leading to different electrocatalytic and capacitive performances. These findings are insightful for the future development and fabrication of advanced flexible electronics with allotropic carbon papers.

The Electrostatic Model of Homeopathy: The Mechanism of Physicochemical Activities of Homeopathic Medicines.

This paper attempts to propose a model, called the electrostatic model of homeopathy, to explain a mechanism for the physicochemical activities of highly diluted homeopathic medicines (HMs). According to this proposed model, the source of HMs' action is dipole orientations as electrostatic imprints of the original molecules carried by diluent molecules (such as sugar molecules) or potentization-induced aqueous nanostructures. The nanoscale domains' contact charging and dielectric hysteresis play critical roles in the aqueous nanostructures' or sugar molecules' acquisition of the original molecules' dipole orientations. The mechanical stress induced by dynamization (vigorous agitation or trituration) is a crucial factor that facilitates these phenomena. After dynamization is completed, the transferred charges revert to their previous positions but, due to dielectric hysteresis, they leave a remnant polarization on the aqueous nanostructures or sugar molecules' nanoscale domains. This causes some nanoscale domains of the aqueous nanostructures or sugar molecules to obtain the original substance molecules' dipole orientations. A highly diluted HM may have no molecule of the original substance, but the aqueous nanostructures or sugar molecules may contain the original substance's dipole orientations. Therefore, HMs can precisely aim at the biological targets of the original substance molecules and electrostatically interact with them as mild stimuli.

Block Copolymer Stabilized Liquid Nanodroplets Facilitate Efficient Triplet Fusion-Based Photon Upconversion in Solid Polymer Matrices.

Sensitized triplet-triplet annihilation-based photon upconversion is a photophysical process that affords anti-Stokes-shifted emission after annihilation of two metastable triplet excitons of an emitter dye and the formation of a fluorescent singlet state. While this process readily occurs in solutions under conditions where the mobility of the dye molecules is high, particular architectures are required to facilitate efficient energy transfers in solid polymers. One possibility is to incorporate liquid upconverting domains into solid polymer matrices. Another possibility is to reduce the intermolecular distance between the dyes below the Dexter radius, allowing exciton migration via triplet hopping. We introduce herein nanostructured materials that combine both of these features. These glassy nanostructured polymer systems contain liquid upconverting nanodroplets that are stabilized with a block copolymer surfactant and are fabricated under ambient conditions in a facile one-step protocol. The dyes concentrate in the nanostructured liquid domains, and this enables hopping-mediated ET and TTA between the dyes and leads to an upconversion efficiency of ∼20%.

Effect of tip radius on the nanoscale viscoelastic measurement of polymers using loss tangent method in amplitude modulation AFM

We study the influence of tip radius on the viscoelastic characterization of polymers using a recently developed loss tangent (tan δ) method operated in amplitude modulation atomic force microscopy (AM-AFM) mode. By decreasing the tip radius, we found that AM-AFM tan δ of a homogeneous polystyrene film decreased close to the bulk limit value, which can be ascribed to a reduced effect of the probe/sample adhesive interaction for a smaller tip. Decreasing the tip radius also shifted the tan δ values of nanostructured blocks in a poly(styrene-b-isoprene-b-styrene) triblock copolymer film to their bulk limits, but in different trends for glassy styrene and rubbery isoprene blocks. Besides minimizing the effect of the adhesive interaction, we demonstrate that reducing the tip radius being smaller than the characteristic size of nanostructured domains is critical to obtain their true tan δ image.

Effective control of solution self-assembly of P3HT/zinc salt complex for in situ template synthesis of P3HT/ZnO nanohybrids

This study explored the detailed solution self-assembly of a P3HT/zinc salt complex system as well as the following in situ growth mechanism of ZnO nanocrystals within self-assembled nanotemplates. Through controlling the solvent selectivity and aging conditions, the geometric shape of the complex system could be directly tailored in solution, forming nanoscopic spheres or highly elongated nanofibrils. These solution self-assembled nanostructures could be efficaciously transferred onto substrates to fabricate nanostructured hybrid films through drop casting. In contrast to traditional P3HT systems with only form Ⅰ crystalline structure, nanostructured P3HT complex thin films revealed a metastable crystalline phase with overlapping alkyl side chains. The formation of this interdigitated crystalline feature could be attributed to the solvent evaporation‐induced crystallization of tightly assembled complex chains existing in solution self-assembled nanostructured domains. The nanostructured P3HT/zinc salt complex assemblies were further used as nanoreactors for the in situ growth of ZnO. As complex samples were thermally treated, a phase transformation of P3HT from the metastable crystalline phase to form Ⅰ structure as well as the formation of ZnO nanocrystals were clearly observed. Both nanospherical and nanofibrillar structured P3HT/ZnO hybrids exhibited lower photoluminescence intensity than did a P3HT/ZnO blend sample. In particular, the nanofibrillar structured hybrid provided an optimized donor/acceptor structure for exciton dissociation as well as interpenetrating nanochannels for charge transport, resulting in the most effective photoluminescence quenching effect among measured samples. We believe that our study can serve as a model system and provide guidelines for efficiently controlling the hierarchical structures of π-conjugated polymer/inorganic nanocrystal hybrids through the in situ synthesis, offering benefits for advanced photoelectronic applications.

Bicontinuous Ion-Exchange Materials through Polymerization-Induced Microphase Separation.

Polymerization-induced microphase separation has been used to prepare solid cross-linked monoliths containing bicontinuous and nanostructured polymer domains. We use this process to fabricate a monolith containing either a negatively or positively charged polyelectrolyte domain inside of the neutral styrene/divinylbenzene-derived matrix. First, the materials are made with a neutral pre-ionic polymer containing masked charged groups. The monoliths are then functionalized to a charged state by treatment with trimethylamine; small-angle X-ray scattering shows no significant morphological change in the microphase-separated structure upon postpolymerization modification. By exchanging dyes with the counterions in the material, we corroborated the continuity of the charged domains. Using ion-exchange capacity measurements, we estimate the number of accessible charges within the material based on macro-chain transfer agent molar mass and loading.