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Concentrated water-in-salt electrolytes (WiSEs) are used in aqueous batteries and to control electrochemical reactions for fuel production. The hydrogen evolution reaction is a parasitic reaction at the negative electrode that limits cell voltage in WiSE batteries and leads to self-discharge, and affects selectivity for electrosynthesis. Mitigating and modulating these processes is hampered by a limited fundamental understanding of HER kinetics in WiSEs. Here, we quantitatively assess how thermodynamics, kinetics, and interface layers control the apparent HER activities in 20 m LiTFSI. When the LiTFSI concentration is increased from 1 to 20 m, an increase in proton activity causes a positive shift in the HER equilibrium potential of 71 mV. The exchange current density, io, derived from the HER branch for 20 m LiTFSI in 98% purity (0.56 ± 0.05 μA/cmPt2), however, is 8 times lower than for 20 m LiTFSI in 99.95% (4.7 ± 0.2 μA/cmPt2) and 32 times lower than for 1 m LiTFSI in 98% purity (18 ± 1 μA/cmPt2), demonstrating that the WiSE's impurities and concentration are both central in significantly suppressing HER kinetics. The ability and applicability of the reported methods are extended by examining additional WiSEs formulations made of acetates and nitrates.

Plasmonic metal/semiconductor heterostructures show promise for visible-light-driven photocatalysis. Gold nanorods (AuNRs) semi-coated with TiO2 are expected to be ideally structured systems for hydrogen evolution. Synthesizing such structures by wet-chemistry methods, however, has proved challenging. Here we report the bottom-up synthesis of AuNR/TiO2 nanodumbbells (NDs) with spatially separated Au/TiO2 regions, whose structures are governed by the NRs' diameter, and the higher curvature and lower density of CnTAB surfactant at the NRs' tips than on their lateral surfaces, as well as the morphology's dependence on concentration, and alkyl chain length of CnTAB. The NDs show plasmon-enhanced H2 evolution under visible and near-infrared light.

Zeolites are crystalline inorganic solids with microporous structures, having widespread applications in the fields of catalysis, separation, adsorption, microelectronics, and medical diagnosis. A major drawback of zeolites is the mass transfer limitation due to the small size of the micropores (less than 1 nm). Numerous efforts have been dedicated to integrating mesopores with the microporous zeolite structures by using templating and/or destructive approaches. Here we provide a new strategy for hierarchical pore size zeolite synthesis, without using supramolecular or hard templates. The branching epitaxial growth behavior, as a result of aluminum-zoning, contributes to the formation of the hierarchical porous zeolite structures.

We have developed a facile procedure that can create asymmetrical building blocks by uniformly deforming nanospheres into C(∞v) symmetry at low cost and high quality. Concave polystyrene@carbon (PS@C) core-shell nanospheres were produced by a very simple microwave-assisted alcohol thermal treatment of spherical PS@C nanoparticles. The dimensions and ratio of the concave part can be precisely controlled by temperature and solvents. The concavity is created by varying the alcohol-thermal treatment to tune the swelling properties that lead to the mechanical deformation of the PS@C core-shell structure. The driving force is attributed to the significant volume increase that occurs upon polystyrene core swelling with the incorporation of solvent. We propose a mechanism adapted from published models for the depression of soft capsules. An extrapolation from this model predicts that the rigid shell is used to generate a cavity in the unbuckled shell, which is experimentally confirmed. This swelling and deformation route is flexible and should be applicable to other polymeric nanoparticles to produce asymmetrical nanoparticles.

Constructing nanoparticles into well-defined structures at mesoscale and larger to create novel functional materials remains a challenge. Inspired by atomic epitaxial growth, we propose an "epitaxial assembly" method to form two-dimensional nanoparticle arrays (2D NAs) directly onto desired materials. As an illustration, we employ a series of surfactant-capped nanoparticles as the "artificial atoms" and layered hybrid perovskite (LHP) materials as the substrates and obtain 2D NAs in a large area with few defects. This method is universal for nanoparticles with different shapes, sizes, and compositions and for LHP substrates with different metallic cores. Raman spectroscopic and X-ray diffraction data support our hypothesis of epitaxial assembly. The novel method offers new insights into the controllable assembly of complex functional materials and may push the development of materials science at the mesoscale.

We describe a general approach for the synthesis of micro-/nanostructured metal chalcogenides from elemental precursors. The excellent solubility of sulfur, selenium, and tellurium in phosphonium ionic liquids promotes fast reactions between chalcogens and various metal powders upon microwave heating, giving crystalline products. This approach is green, universal, and scalable.

The combination of electrostatic affinities and hydrogen bonding between the poly-L-lysine and the critic acid-functionalized QDs creates a zone of water exclusion around each nanoparticle. Excess number of positive charges associated with the polymer relative to the number of carboxylic acid groups (pK3) is required for these vesicles to form and therefore the initially negative charged pK3 carboylic acid group of the citrate-coated QDs is effectively neutralized after reaction with the polypeptide.

The synthesis of new mesoporous silica structures using low molecular weight nonionic ethylene oxide surfactants and poly(alkylene oxide) block copolymers in acid media is described. Results showed that the selected surfactant species not only influence the structure of ordered mesoporous silica, each surfactant type also plays a role in the formation of a specific mesostructured silica phase. It was also observed that the silica formed were highly ordered and thermally stable even in boiling water.

Ordered, lamellar, iron oxide/surfactant composites with varied iorn oxide layer thicknesses, were synthesized and characterized. Controlled precipitation and hydrolysis of aqueous iron cations was used to prepare the new materials, with redox chemistry to alter the iron oxide solubility. X-ray diffraction determined the layered structre of the composites, produced with about three to almost 20 A of iron oxide, alternated with surfactant bilayers.

The syntheses and characterizations of chiral tetrahedral cobalt phosphate compounds: MCoPO4 (M=Na, K, NH4, Rb) as well as the different types of framework structures have been described. One of the structures has the same topology as the zeolite ABW framework and the other cobalt phosphate can be viewed as a hybrid of tridymite and ABW frameworks. The cobalt phosphate compounds can be synthesized under hydrothermal conditions and their frameworks are more flexible than aluminosilicate in adapting cations of different sizes.

Nonstoichiometric silver,sodium bromosodalites, which allow the control of filling both silver and X ions in a sodalite host lattice in a sytematic manner to fabricate Na4-nAgnX semiconductor-component clusters, were synthesized. Spectrum analysis indicate that these halosodalites form a solid solution of Na3-mAgm clusters in anion-free beta cages interspersed with Na4-nAgnX clusters. In addition, the clusters are statistically distributed throughout the lattice.

Sodium sodalites of the composition Na8X2(SiAlO4)6, where X = Cl1-, Br1- and I1-, were prepared by a low-temperature hydrothermal synthesis. The Na1+ ions were replaced with Ag1+ ions via AgNO3 melt and hydrothermal aqueous exchanges. Results showed that unit cell sizes of class A sodalites are influenced by silver concentration andhalide type. Low silver concentrations result in short Ag-X distances, while high Ag1+ concentrations up to complete exchange result in a sodalite lattice possessing an expanded silver halide.

A magnesiothermic reduction synthesis approach is described for direct conversion of Si[O.sub.2]/C composite nanostructures to corresponding SiC materials without losing their nanostructure morphologies. An ordered hierarchical macro-mesoporous SiC material is prepared and the pseudomorphic transformation is regarded as a general synthesis method for different kinds of SiC nanostructures, which is extended to other metal carbide materials as well as TiC.

Mesoporous mixed metal oxide (K-Cu-Ti[O.sub.2]) catalyst is capable of highly selective, gas-phase benzyl alcoholbenzaldehyde transformation under low temperatures. The low-temperature reaction conditions and integration of K and Cu(I) components into the Ti[O.sub.2] matrix are very important for the stabilization of an active Cu(I) oxidation state and resultant stable, excellent catalytic performance.

An unprecedented type of ordered mesoporous material with a hexagonally pillared lamellar (HPL) structure (P[6.sub.3]/mmc) that could be synthesized via a phase transformation from a lamellar mesophase by hydrothermal reaction in the presence of an organosilica precursor and a high concentration of a designed Gemini surfactant ([Gem.sub.16-3-16]) that have a large g value is reported. The GMO-HPL which have a unique three-dimensional periodic structure with two-dimensionally connected pore channels running between the framework layers, provides a fascinating topological link between the lamellar and columnar (2D hexagonal) mesophases.

A facile nonaqueous synthetic route is described for preparing anatase nanosheets with exposed {001} facets and high-quality rhombic-shaped anatase nanocrystals with a large percentage of exposed {010} facets. The nanostructured Ti[O.sub.2] has displayed conspicuous activity in the photocatalytic degradation of organic contaminants.

The development and the mechanisms involved in one- and two-photon induced polymerization of methylmethacrylate using colloidal CdS semiconductor quantum dots (QDs) is presented. The efficiency of the photopolymerization process is shown to highly increase by the co-initiators.

A large-scale and versatile synthetic approach is described for obtaining porous carbon and porous carbon/hollow metal oxide microfibers with uniform and tunable pore sizes and well-defined carbon/metal oxide interfaces by using an ice-templating strategy. These porous carbon and carbon/metal oxide composite fibers are shown to be promising candidates for a wide range of applications.

The article discusses the reversible addition fragmentation chain transfer (RAFT) process, which is commonly used for the synthesis of various well-defined, double hydrophilic block copolymers and nanostructured hydrogels.

A general strategy to prepare oxide-supported metal nanoparticle catalysts that could be used in acidic and basic oxides was developed. The method was successfully applied to develop green, efficient gold catalysts like the selective oxidation of ethanol by oxygen.

A facile one-step one-phase synthetic route to achieve a variety of metallic nanoparticles by using amine-borane complexes as reducing agent is reported. The use of amine-borane complexes as reducing agents and thiols as capping ligands is essential to the synthetic route reported.

A high-optical-quality titania-based mesostructured film with cubic or 2D-hexagonal symmetry is fabricated. The results revealed that trifluoroacetate (TFA) coordinates the titanium center and forms a stable complex that is subsequently organized by the block copolymer species into ordered mesostructures.

The formation SiO2 / gold nanoparticals based hollow microspheres with the help of dye-tagged poly(L-lysine) (PLL) is described. Structural analysis indicates that the PLL is located in the interior of the hollow sphere within the silica shell wall.

A new type of Gemini surfactant containing a siloxane moiety, which can yield highly stable mesoporous metal oxides after the removal of the surfactant via the nano-propping pathway, is described. Structures of the Gemini surfactant and a schematic diagram for the nano-propping pathway are presented.

The hexagonally organized mesoporous silica nanofibers are synthesized. These nanofibers possess a circular or longitudinal pore architecture, which can be readily controlled via the synthesis.

A novel strategy is reported for controlled preparation of cross-linked polymeric nanoparticles (NPs). The cross-linkers with enhanced reactivity and controlled microwave reaction procedures have proved to be powerful tool for the synthesis of cross-linked, functionalized NPs under high solids content and surfactant-free conditions.

The tunable invitro hemostatic activity of high-surface-area hemostatic bioactive glass (BG) is evaluated with Thromboelastograph, a standard medical instrument for quantifying viscoelasticity changes of blood during thrombosis and fibrinolysis. The investigation of the effect of particle morphology, and preliminary result reveal that size and shape are key clotting parameters.

A simple approach for the selective shortening of single-crystalline Au NRs (gold nanorods) by mild oxidation with environmentally benign oxygen is reported. This shortening method could be used to produce Au NRs of any desired aspect ratio with narrow size distributions within the limit of that possessed by starting NRs.

The vesicle array-templated surface patterning of microscale silica features, including convex protrusions, concave depressions and their combinations, which can be synthetically controlled is demonstrated. These surface patterns can function as arrays of microlens that are capable of producing numerous images from a common object.

The synthesis of hybrid mesostructured materials utilizing a fluorocarbon-stabilized titania precursor is described. Applications in optical switches, sensors and low threshold waveguide microlasers are found.

Benzyl alcohol and TiCL4 provide an unprecedentedly versatile reaction system for the preparation of spherical 'quasi' zero-dimensional titania nanoparticles. The reaction between transition metal chlorides and benzyl alcohol leads to low-dimensional particle shapes such as nearly spherical titania nanoparticles, vanadium oxide nanorods, and tungsten oxide nanoplatelets.

Nanostructured ZnO films utilizing cooperative surface assembly of surfactants and inorganic species are electrodeposited under the influence of an electrostatic potential. This approach effectively manipulates surfactant - inorganic aggregates at low concentration in solution to generate high-quality nanostructured films.

Research has been conducted on the cubic mesopurous single crystals. The synthesis of these crystals has been carried out under acidic conditions via the nonionic block copolymer used as a template.

An open framework material is described, with dangling carboxylic functional groups within 24-ring channels.

A method to synthesize periodic mesoporous silica through direct liquid crystal templating is described.

Research is presented describing the sequestration of anionic proteins, by SBA-15 and MCF, from aqueous solutions. The release of sequestered proteins by an increase of ionic strength is reported. The techniques of size exclusion and ion-exchange chromatography are employed simultaneously.

The induction of phase transformations from the highly ordered p6mm mesostructure of SBA-15-type mesoporous silicas to mesostructured cellular foams or mesocellular foams (MCF) by the addition of large amounts of organic cosolvents were described. The MCF were made of uniform, large spherical cells interconnected by uniform windows to develop a continuous 3-D pore system. The well-defined MCF pore structure was accurately described by nitrogen sorption measurements.

The limited success in the formation of silicate-based 3-ring structures may be due to the short Si-O bond distance and the corresponding large T-O-T angles that do not favor the highly stressed 3-ring configuration relative to rings of bigger sizes. To produce new 3-ring structures, the geometrical factors for reducing the stress found in a 3-ring structure have to be considered. The first 3-ring-containing germanates have been synthesized and their structures are shown.

Surface silanol groups of mosoporous materials provide good anchoring sites for grafting organic moieties or transition metal ions for chemical sensors or catalytic applications. Transition-metal-associated mesoporous materials can create reaction sites and molecular confinement. Catalytic halogenation reactions are currently undertaken with haloperoxidase enzymes, such as vanadium bromoperoxidase (V-BrPO), which catalyzes the bromination of several organic substrates.

The synthesis, crystal growth and single crystal structure of a microporous sodium zincarbonate is reported. The open framework structure is characterized by a diamond-type tetrahedral-triangular topology and prepared as a microcrystalline powder by slowly adding NaHCO3 to ZnCl2. The crystals are stable in air and moisture but dissolve in dilute acid. Its asymmetric unit has two crystallographically different carbon and sodium atom sites.