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Strong metal–support interactions (SMSIs) are well-known in the field of heterogeneous catalysis to induce the encapsulation of platinum (Pt) group metals by oxide supports through high temperature H2reduction. However, demonstrations of SMSI overlayers have largely been limited to reducible oxides, such as TiO2and Nb2O5. Here, we show that the amorphous native surface oxide of plasmonic aluminum nanocrystals (AlNCs) exhibits SMSI-induced encapsulation of Pt following reduction in H2in a Pt structure dependent manner. Reductive treatment in H2at 300 °C induces the formation of an AlOxSMSI overlayer on Pt clusters, leaving Pt single-atom sites (Ptiso) exposed available for catalysis. The remaining exposed Ptisospecies possess a more uniform local coordination environment than has been observed on other forms of Al2O3, suggesting that the AlOxnative oxide of AlNCs presents well-defined anchoring sites for individual Pt atoms. This observation extends our understanding of SMSIs by providing evidence that H2-induced encapsulation can occur for a wider variety of materials and should stimulate expanded studies of this effect to include nonreducible oxides with oxygen defects and the presence of disorder. It also suggests that the single-atom sites created in this manner, when combined with the plasmonic properties of the Al nanocrystal core, may allow for site-specific single-atom plasmonic photocatalysis, providing dynamic control over the light-driven reactivity in these systems.

A combination of nonionic, cationic, and zwitterionic surfactants is shown both to stabilize the transmembrane protein proteorhodopsin, as well as to direct coassembly into robust transparent mesostructured silica–surfactant films containing high loadings of functionally active protein guests. Proteorhodopsin is a transmembrane protein that exhibits light-activated H+transport properties, the photocycle kinetics of which are quantified by time-resolved UV–visible spectroscopy and demonstrated to be similar to proteorhodopsin in the abiotic mesostructured films compared to native-like lipids. The surfactants mediate the pKaof a key ion-channel residue, leading to an expanded pH functional range for proteorhodopsin in mesostructured silica–surfactant host materials. Small-angle X-ray diffraction results for 100-μm films show high extents of mesoscale order with protein loadings up to 25 wt % and wormlike mesostructural order for 44 wt % proteorhodopsin. Solid-state 1H, 13C, and 29Si NMR analyses provide atomic-scale insights into the compositions and interactions at the mesochannel surfaces, which account for the structure-directing roles of surfactant species. Nanoindentation measurements reveal the mechanical robustness of the films, which interestingly increases with proteorhodopsin loading for the compositions examined. Heat treatment analyses show improved thermal stability for proteorhodopsin to 110 °C within mesostructurally ordered films. The results establish closely correlated relationships between the compositions, nano- and mesoscale structures, photocycle kinetics, and macroscopic mechanical properties and thermal stabilities of the silica–surfactant- proteorhodopsin films, providing key biomimetic design criteria.

The distributions of heteroatoms within zeolite frameworks have important influences on the locations of exchangeable cations, which account for the diverse adsorption and reaction properties of zeolite catalysts. In particular for aluminosilicate zeolites, paired configurations of aluminum atoms separated by one or two tetrahedrally coordinated silicon atoms are important for charge-balancing pairs of H+cations, which are active for methanol dehydration, or divalent metal cations, such as Cu2+, which selectively catalyze the reduction of NOx, both technologically important reactions. Such paired heteroatom configurations, however, are challenging to detect and probe, due to the typically nonstoichiometric compositions and nonperiodic distributions of aluminum atoms within aluminosilicate zeolite frameworks. Nevertheless, distinct configurations of paired framework aluminum atoms are unambiguously detected and resolved in solid-state 2D 27Al–29Si and 29Si–29Si NMR spectra, which are sensitive to the local environments of covalently bonded 27Al–O–29Si and 29Si–O–29Si moieties, respectively. Specifically, two H+-chabazite zeolites with the same bulk framework aluminum contents are shown to have different types and populations of closely paired aluminum species, which correlate with higher activity for methanol dehydration. The methodologies and insights are expected to be broadly applicable to analyses of heteroatom sites, their distributions, and adsorption and reaction properties in other zeolite framework types.

The functional properties of proteorhodopsin (PR) have been found to be strongly modulated by oligomeric distributions and lipid membrane mimetics. This study aims to distinguish and explain their effects by investigating how oligomer formation impacts PR’s function of proton transport in lipid-based membrane mimetic environments. We find that PR forms stable hexamers and pentamers in both E. colimembranes and synthetic liposomes. Compared with the monomers, the photocycle kinetics of PR oligomers is ∼2 and ∼4.5 times slower for transitions between the Kand Mand the Mand Nphotointermediates, respectively, indicating that oligomerization significantly slows PR’s rate of proton transport in liposomes. In contrast, the apparent pKa of the key proton acceptor residue D97 (pKaD97) of liposome-embedded PR persists at 6.2–6.6, regardless of cross-protomer modulation of D97, suggesting that the liposome environment helps maintain PR’s functional activity at neutral pH. By comparison, when extracted directly from E. colimembranes into styrene-maleic acid lipid particles, the pKaD97of monomer-enriched E50Q PR drastically increases to 8.9, implying that there is a very low active PR population at neutral pH to engage in PR’s photocycle. These findings demonstrate that oligomerization impacts PR’s photocycle kinetics, while lipid-based membrane mimetics strongly affect PR’s active population via different mechanisms.

To understand the nature and structure of N-doping centers in carbon materials, we combine two-dimensional (2D) solid-state NMR experiments and chemical shift calculations for 15N, 13C, and 1H nuclei from density functional theory (DFT). Comparisons of predicted chemical shifts with experimental 2D 13C–15N spectra show good agreement and the calculations explain the spectral broadening seen in the experiments. The major differences between the chemical shifts of graphitic/pyridinic/pyrrolic N-moieties are understood by comparing the electronegativities of the various environments. Moreover, the signal broadening is explained using four different factors: (1) the standalone N/C geometry, (2) the effect of a second N atom nearby, (3) the first or second neighbor C atom difference, and (4) the influence of residual water, which is important to understand the electrocatalytic environment. An intuitive correlation between the charge of the probed atom and the chemical shift is validated: the smaller the charge, i.e., higher electron density, the more shielded the nucleus is, and hence the smaller the associated chemical shift. These results can improve the understanding of the nature of heteroatom sites in nitrogen–carbon materials and contribute to the rational design of these materials with desired electronic properties and improved electrochemical performance.

Organic structure-directing agents (OSDAs) are exploited in the crystallization of microporous materials to tailor the physicochemical properties of the resulting zeolite for applications ranging from separations to catalysis. The rational design of these OSDAs often entails the identification of molecules with a geometry that is commensurate with the channels and cages of the target zeolite structure. Syntheses tend to employ only a single OSDA, but there are a few examples where two or more organics operate synergistically to yield a desired product. Using a combination of state-of-the-art characterization techniques and molecular modeling, we show that the coupling of N,N,N-trimethyl-1,1-adamantammonium and 1,2-hexanediol, each yielding distinct zeolites when used alone, results in the cooperative direction of a third structure, HOU-4, with the mordenite framework type (MOR). Rietveld refinement using synchrotron X-ray diffraction data reveals the spatial arrangement of the organics in the HOU-4 crystals, with amines located in the large channels and alcohols oriented in the side pockets lining the one-dimensional pores. These results are in excellent agreement with molecular dynamics calculations, which predict similar spatial distributions of organics with an energetically favorable packing density that agrees with experimental measurements of OSDA loading, as well as with solid-state two-dimensional 27Al{29Si}, 27Al{1H}, and 13C{1H} NMR correlation spectra, which establish the proximities and interactions of occluded OSDAs. A combination of high-resolution transmission electron microscopy and atomic force microscopy is used to quantify the size of the HOU-4 crystals, which exhibit a platelike morphology, and to index the crystal facets. Our findings reveal that the combined OSDAs work in tandem to produce ultrathin, nonfaulted HOU-4 crystals that exhibit improved catalytic activity for cumene cracking in comparison to mordenite crystals prepared via conventional syntheses. This novel demonstration of cooperativity highlights the potential possibilities for expanding the use of dual structure-directing agents in zeolite synthesis.

Boron adsorption properties of poly(styrene-co-divinylbenzene) (PSDVB)-based anion-exchange resins with surface-grafted N-methyl-d-glucamine (NMDG) depend strongly on their local surface compositions, structures, and interfacial interactions. Distinct boron adsorption sites have been identified and quantified, and interactions between borate anions and hydroxyl groups of NMDG surface moieties have been established. A combination of X-ray photoelectron spectroscopy (XPS), solid-state nuclear magnetic resonance (NMR), and Fourier-transform infrared (FT-IR) spectroscopy were used to characterize the atomic-level compositions and structures that directly influence the adsorption of borate anions on the NMDG-functionalized resin surface. Surface-enhanced dynamic-nuclear-polarization (DNP)-NMR enabled dilute (3 atom % N) tertiary alkyl amines and quaternary ammonium ions of the NMDG groups to be detected and distinguished with unprecedented sensitivity and resolution at natural abundance 15N (0.4%). Two-dimensional (2D) solid-state 11B{1H}, 13C{1H}, and 11B{11B} NMR analyses provide direct atomic-scale evidence for interactions of borate anions with the NMDG moieties on the resin surfaces, which form stable mono- and bischelate complexes. FT-IR spectra reveal displacements in the stretching vibrational frequencies associated with the O–H and N–H bonds of NMDG groups that corroborate the formation of chelate complexes on the resin surfaces. The atomic-level compositions and structures are related to boron adsorption properties of resin materials synthesized under different conditions, which have important remediation applications.

Dissolution of mineral surfaces at asymmetric solid–liquid–solid interfaces in aqueous solutions occurs in technologically relevant processes, such as chemical/mechanical polishing (CMP) for semiconductor fabrication, formation and corrosion of structural materials, and crystallization of materials relevant to heterogeneous catalysis or drug delivery. In some such processes, materials at confined interfaces exhibit dissolution rates that are orders of magnitude larger than dissolution rates of isolated surfaces. Here, the dissolution of silica and alumina in close proximity to a charged gold surface or mica in alkaline solutions of pH 10–11 is shown to depend on the difference in electrostatic potentials of the surfaces, as determined from measurements conducted using a custom-built electrochemical pressure cell and a surface forces apparatus (SFA). The enhanced dissolution is proposed to result from overlap of the electrostatic double layers between the dissimilar charged surfaces at small intersurface separation distances (<1 Debye length). A semiquantitative model shows that overlap of the electric double layers can change the magnitude and direction of the electric field at the surface with the less negative potential, which results in an increase in the rate of dissolution of that surface. When the surface electrochemical properties were changed, the dissolution rates of silica and alumina were increased by up to 2 orders of magnitude over the dissolution rates of isolated compositionally similar surfaces under otherwise identical conditions. The results provide new insights on dissolution processes that occur at solid–liquid–solid interfaces and yield design criteria for controlling dissolution through electrochemical modification, with relevance to diverse technologies.

The structure of the calcined form of the high-silica zeolite SSZ-70 has been elucidated by combining synchrotron X-ray powder diffraction (XRPD), high resolution transmission electron microscopy (HRTEM), and two-dimensional (2D) dynamic nuclear polarization (DNP)-enhanced NMR techniques. The framework structure of SSZ-70 is a polytype of MWWand can be viewed as a disordered ABC-type stacking of MWW-layers. HRTEM and XRPD simulations show that the stacking sequence is almost random, with each layer being shifted by ±1/3 along the <110> direction with respect to the previous one. However, a small preponderance of ABAB stacking could be discerned. DNP-enhanced 2D 29Si{29Si} J-mediated NMR analyses of calcined Si-SSZ-70 at natural 29Si isotopic abundance (4.7%) establish the through-covalent-bond 29Si-O-29Si connectivities of distinct Si sites in the framework. The DNP-NMR results corroborate the presence of MWW-layers and, more importantly, identify two distinct types of Q3silanol species at the surfaces of the interlayer regions. In the first, an isolated silanol group protrudes into the interlayer space pointing towards the pocket in the adjacent layer. In the second, the surrounding topology is the same, but the isolated -SiOH group is missing, leaving a nest of three Si-O-H groups in place of the three Si-O-Si linkages. The analyses clarify the structure of this complicated material, including features that do not exhibit long-range order. With these insights, the novel catalytic behavior of SSZ-70 can be better understood and opportunities for enhancement recognized.

Semiconducting polymers provide a ubiquitous platform for a range of applications in molecular electronics and photovoltaics, but the ordered and disordered regions of these materials impart different optoelectronic properties. By resolving local morphology using solid-state magnetic resonance spectroscopy and modeling techniques, here, we demonstrate that the PTB7-Th donor–acceptor (D–A) copolymer and P3HT and MEH-PPV homopolymers exhibit different degrees of the short-range order, which can be associated with the large differences in their charge carrier mobilities. The high degree of local order in PTB7-Th (84–99%) is facilitated by noncovalent interactions between D and A moieties. In contrast to this, the reduced local order in P3HT (30–44%) and MEH-PPV (39–43%) homopolymers is due to the distortions in the vicinities of backbone and side chain moieties that lead to conformationally tilted polymer chains. Combined solid-state NMR and density functional theory (DFT) modeling allows the degree of backbone torsion in these materials to be determined, and insights into packing interactions are obtained by two-dimensional (2D) 1H–1H, 1H–13C, and 1H–19F correlation NMR spectroscopy. In addition, the different paramagnetic species and hyperfine interactions are analyzed by EPR spectroscopy and are expected to influence the charge carrier mobilities. A detailed analysis of the local structures presented in this study helps explain the morphological anomalies and their impact on bulk charge carrier mobilities and electronic density of states, thus providing essential insights into the morphology–property relationships in polymeric organic semiconductors.

In this report, we investigate the binding properties of the Lewis acid tris(pentafluorophenyl)borane with a Lewis base semiconducting polymer, PFPT, and the subsequent mechanism of band gap reduction. Experiments and quantum chemical calculations confirm that the formation of a Lewis acid adduct is energetically favorable (ΔG° < −0.2 eV), with preferential binding at the pyridyl nitrogen in the polymer backbone over other Lewis base sites. Upon adduct formation, ultraviolet photoelectron spectroscopy indicates only a slight decrease in the HOMO energy, implying that a larger reduction in the LUMO energy is primarily responsible for the observed optical band gap narrowing (ΔEopt= 0.3 eV). Herein, we also provide the first spatially resolved picture of how Lewis acid adducts form in heterogeneous, disordered polymer/tris(pentafluorophenyl)borane thin films via one- (1D) and two-dimensional (2D) solid-state nuclear magnetic resonance. Notably, solid-state 1D 11B, 13C{1H}, and 13C{19F} cross-polarization magic-angle spinning (CP-MAS) NMR and 2D 1H{19F} and 1H{1H} correlation NMR analyses establish that BCF molecules are intercalated between branched C16H33side chains with the boron atom facing toward the pyridyl nitrogen atoms of PFPT.

The diverse functionalities of membrane proteins (MPs) have garnered much interest in leveraging these biomolecules for technological applications. One challenge of studying MPs in artificial micellar surfactant environments is that many factors modulate their structures and functionalities, including the surfactants that interact with the MP or their assembly into oligomers. As oligomerization offers a means by which MPs could selectively interact among the copious environmental factors in biological environments, we hypothesized that MP function is predominantly modified by oligomerization rather than interactions with local surfactants that, by comparison, largely interact with MPs nonspecifically. To test this, we study the light-activated proton pump proteorhodopsin (PR) in micellar surfactant solutions because it is functionally active in monomeric and oligomeric forms, the light-activated functionalities of which can be assessed in detail. The surfactant composition and oligomerization are correlated with PR function, as measured by the protonation behaviors of aspartic acid residue 97, which mediates light-activated proton transport, and the associated photocycle kinetics. The results demonstrate that oligomerization dominantly mediates PR function in different surfactant environments, whereas some surfactants can subtly modulate proton-pumping kinetics. This work underscores the importance of understanding and controlling oligomerization of MPs to study and exploit their function.

Cube-shaped nanocrystals (NCs) of conventional metals like gold and silver generally exhibit localized surface plasmon resonance (LSPR) in the visible region with spectral modes determined by their faceted shapes. However, faceted NCs exhibiting LSPR response in the infrared (IR) region are relatively rare. Here, we describe the colloidal synthesis of nanoscale fluorine-doped indium oxide (F:In2O3) cubes with LSPR response in the IR region, wherein fluorine was found to both direct the cubic morphology and act as an aliovalent dopant. Single-crystalline 160 nm F:In2O3cubes terminated by (100) facets and concave cubes were synthesized using a colloidal heat-up method. The presence of fluorine was found to impart higher stabilization to the (100) facets through density functional theory calculations that evaluated the energetics of F-substitution at surface oxygen sites. These calculations suggest that the cubic morphology results from surface binding of F atoms. In addition, fluorine acts as an anionic aliovalent dopant in the cubic bixbyite lattice of In2O3, introducing a high concentration of free electrons leading to LSPR. We confirmed the presence of lattice fluorine dopants in these cubes using solid-state 19F and 115In nuclear magnetic resonance spectroscopy. The cubes exhibit narrow, shape-dependent multimodal LSPR extinction peaks due to corner- and edge-centered modes. The spatial origin of these different contributions to the spectral response is directly visualized by electron energy loss spectroscopy in a scanning transmission electron microscope.

High-performance organic semiconducting materials are reliant upon subtle changes in structure across different length scales. These morphological features control relevant physical properties and ultimately device performance. By combining in situNMR spectroscopy and theoretical calculations, the conjugated small molecule TT is shown to exhibit distinct temperature-dependent local structural features that are related to macroscopic properties. Specifically, lamellar and melt states are shown to exhibit different molecular topologies associated with planar and twisted conformations of TT, respectively. This topological transformation offers a novel avenue for molecular design and control of solid-state organization.

Tailorable sorption properties at the molecular level are key for efficient carbon capture and storage and a hallmark of covalent organic frameworks (COFs). Although amine functional groups are known to facilitate CO2uptake, atomistic insights into CO2sorption by COFs modified with amine-bearing functional groups are scarce. Herein, we present a detailed study of the interactions of carbon dioxide and water with two isostructural hydrazone-linked COFs with different polarities based on the 2,5-diethoxyterephthalohydrazide linker. Varying amounts of tertiary amines were introduced in the COF backbones by means of a copolymerization approach using 2,5-bis(2-(dimethylamino)ethoxy)terephthalohydrazide in different amounts ranging from 25 to 100% substitution of the original DETH linker. The interactions of the frameworks with CO2and H2O were comprehensively studied by means of sorption analysis, solid-state NMR spectroscopy, and quantum-chemical calculations. We show that the addition of the tertiary amine linker increases the overall CO2sorption capacity normalized by the surface area and of the heat of adsorption, whereas surface areas and pore size diameters decrease. The formation of ammonium bicarbonate species in the COF pores is shown to occur, revealing the contributing role of water for CO2uptake by amine-modified porous frameworks.

The synthesis, characterization, and electrocatalytic properties of mesoporous carbon materials doped with nitrogen atoms and iron are reported and compared for the catalyzed reduction of oxygen gas at fuel cell cathodes. Mixtures of common and inexpensive organic precursors, melamine, and formaldehyde were pyrolyzed in the presence of transition-metal salts (e.g., nitrates) within a mesoporous silica template to yield mesoporous carbon materials with greater extents of graphitization than those of others prepared from small-molecule precursors. In particular, Fe,N-doped carbon materials possessed high surface areas (∼800 m2/g) and high electrical conductivities (∼19 S/cm), which make them attractive for electrocatalyst applications. The surface compositions of the mesoporous Fe,N-doped carbon materials were postsynthetically modified by acid washing and followed by high-temperature thermal treatments, which were shown by X-ray photoelectron spectroscopy to favor the formation of graphitic and pyridinic nitrogen moieties. Such surface-modified materials exhibited high electrocatalytic oxygen reduction activities under alkaline conditions, as established by their high onset and half-wave potentials (1.04 and 0.87 V, respectively vs reversible hydrogen electrode) and low Tafel slope (53 mV/decade). These values are superior to many similar transition-metal- and N-doped carbon materials and compare favorably with commercially available precious-metal catalysts, e.g., 20 wt % Pt supported on activated carbon. The analyses indicate that inexpensive mesoporous Fe,N-doped carbon materials are promising alternatives to precious metal-containing catalysts for electrochemical reduction of oxygen in polymer electrolyte fuel cells.

When the dominant rate-mechanisms within a mixed-suspension mixed-product removal (MSMPR) crystallizer are secondary nucleation and size-independent linear crystal growth, the effluent crystal distribution is guaranteed to exhibit a single polymorphic solid form at steady state. However, multiple solid forms are often simultaneously observed during the continuous precipitation of CaCO3. Accounting for agglomeration within the population balance reconciles model predictions with experiments. Here, we elucidate the steady state structure and linear stability features of an agglomeration-enabled continuous precipitator model. We demonstrate that one can make rational process design and operation decisions to select the effluent solid form, regardless of its thermodynamic stability. Specifically, we utilize these results to choose process conditions that yield pure, thermodynamically metastable vaterite during CaCO3precipitation, based on powder X-ray diffraction, solid-state 43Ca NMR, and scanning electron microscopy. This new design framework enables predictive modeling of CaCO3precipitation, but more generally, it is expected to enable rational decision making during the design and operation of other agglomerative precipitation processes for which solid form selection is desired.

Cation–π interactions drive the self-assembly and cohesion of many biological molecules, including the adhesion proteins of several marine organisms. Although the origin of cation–π bonds in isolated pairs has been extensively studied, the energetics of cation–π-driven self-assembly in molecular films remains uncharted. Here we use nanoscale force measurements in combination with solid-state NMR spectroscopy to show that the cohesive properties of simple aromatic- and lysine-rich peptides rival those of the strong reversible intermolecular cohesion exhibited by adhesion proteins of marine mussel. In particular, we show that peptides incorporating the amino acid phenylalanine, a functional group that is conspicuously sparing in the sequences of mussel proteins, exhibit reversible adhesion interactions significantly exceeding that of analogous mussel-mimetic peptides. More broadly, we demonstrate that interfacial confinement fundamentally alters the energetics of cation–π-mediated assembly: an insight that should prove relevant for diverse areas, which range from rationalizing biological assembly to engineering peptide-based biomaterials.

The performances of hybrid organic–inorganic photovoltaics composed of conjugated polymers and metal oxides are generally limited by poor electronic coupling at hybrid interfaces. In this study, physicochemical interactions and bonding at the organic–inorganic interfaces are promoted by incorporating organoruthenium dye molecules into self-assembled mesostructured conjugated polymer–titania composites. These materials are synthesized from solution in the presence of surfactant structure-directing agents (SDA) that solubilize and direct the nanoscale compositions and structures of the conjugated polymer, dye, and inorganic precursor species. Judicious selection of the SDA and dye species, in particular, exploits interactions that direct the dye species to the inorganic–organic interfaces, leading to significantly enhanced electronic coupling, as well as increased photoabsorption efficiency. This is demonstrated for the hydrophilic organoruthenium dye N3, used in conjunction with alkyleneoxide triblock copolymer SDA, polythiophene conjugated polymer, and titania species, in which the N3 dye species are localized in molecular proximity to and interact strongly with the titania framework, as established by solid-state NMR spectroscopy. In contrast, a closely related but more hydrophobic organoruthenium dye, Z907, is shown to interact more weakly with the titania framework, yielding significantly lower photocurrent generation. The strong SDA-directed N3-TiOxinteractions result in a significant reduction of the lifetime of the photoexcited state and enhanced macroscopic photocurrent generation in photovoltaic devices. This study demonstrates that multicomponent self-assembly can be harnessed for the fabrication of hierarchical materials and devices with nanoscale control of chemical compositions and surface interactions to improve photovoltaic properties.

Hydrophobic interactions constitute one of the most important types of nonspecific interactions in biological systems, which emerge when water molecules rearrange as two hydrophobic species come close to each other. The prediction of hydrophobic interactions at the level of nanoparticles (Brownian objects) remains challenging because of uncontrolled diffusive motion of the particles. We describe here a general methodology for solvent-induced, reversible self-assembly of gold nanoparticles into 3D clusters with well-controlled sizes. A theoretical description of the process confirmed that hydrophobic interactions are the main driving force behind nanoparticle aggregation.

Graft copolymers with poly(vinyl acetate) (PVAc) backbones and poly(dimethylsiloxane) (PDMS) or poly(styrene) (PS) branches have been synthesized and their bulk nanophase-separation behaviors characterized. The PDMS and PS branches were prepared by anionic polymerization of hexamethylcyclotrisiloxane (D3) and styrene, respectively, followed by termination with chlorodimethylvinylsilane. Radical copolymerization of vinyl acetate with the vinyl terminus of these macromonomers yielded the PVAc-g-PDMS (1) and PVAc-g-PS (2a–d) graft copolymers. The branch repeat units of the copolymers were varied between 19 and 41mol%. The graft copolymers were predicted to be moderately to strongly nanophase-segregated systems at room temperature by estimating the Flory–Huggins interaction parameters (χ) for the polymer segments. Thermal analyses revealed two glass transition temperatures for the PVAc and PDMS or PS polymer segments of the annealed samples, indicating that the polymer segments were locally phase-separated in the bulk phase. Transmission electron micrographs confirmed the presence of nanophase-separated PDMS- or PS-rich domains imbedded in a PVAc matrix.

This short review is intended to direct the reader to selected current literature where mesostructured (typically surfactant templated) materials have been characterized in terms of their potential applications. Only limited experimental data will be presented. However, one of the primary criteria in the literature selection for this review was that the research be closely related to an application, and ideally have some “figure of merit” results which could be directly correlated with current state of the art commercial performance. The use of mesostructured catalysts, while industrially very important, will not be covered since it is presented elsewhere in this volume.