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Recent advances in the sol-gel process derived resorcinol-formaldehyde (RF) coating strategies offer new opportunities for the synthesis and applications of hollow carbon spheres (HCS). Due to the lack of an effective route for controlling the pore structures, the synthesis of RF resin derived HCS with a high specific surface area for promising applications is still a challenge. In this work, we present a facile and effective template-directed multiple coating route to synthesize RF resin derived HCS with foam-like shells (HCSF). The as-synthesized HCSF exhibit a significantly higher specific surface area (1286 m[sup 2] g[sup -1]) and larger pore volumes (2.25 cm[sup 3] g[sup -1]) than the RF resin derived HCS (639 m[sup 2] g[sup -1] and 0.56 cm[sup 3] g[sup -1]). Our experiments demonstrated that the cationic surfactant CTAB plays a critical role in forming the foam-like pore structure. Compared with the RF resin derived HCS, the as-synthesized HCSF show advantageous performances in supercapacitor and confined catalysis due to their unique pore structures. [ABSTRACT FROM AUTHOR]

Ultrathin metal films can exhibit quantum size and surface effects that give rise to unique physical and chemical properties. Metal films containing just a few layers of atoms can be fabricated on substrates using deposition techniques, but the production of freestanding ultrathin structures remains a significant challenge. Here we report the facile synthesis of freestanding hexagonal palladium nanosheets that are less than 10 atomic layers thick, using carbon monoxide as a surface confining agent. The as-prepared nanosheets are blue in colour and exhibit a well-defined but tunable surface plasmon resonance peak in the near-infrared region. The combination of photothermal stability and biocompatibility makes palladium nanosheets promising candidates for photothermal therapy. The nanosheets also exhibit electrocatalytic activity for the oxidation of formic acid that is 2.5 times greater than that of commercial palladium black catalyst. [ABSTRACT FROM AUTHOR]

Magnetic core-shell Fe3O4@SiO2@poly(styrene-alt-maleic anhydride) spheres enriched with Ni-NTA on their surface have been prepared by precipitation polymerization. The spheres have a core composed of superparamagnetic polycrystalline magnetite having a uniform size of ∼220 nm, endowing the spheres with excellent magnetic responsivity and dispersity. The shell composition of poly(styrene-alt-maleic anhydride) allows the incorporation of more Ni-NTA affinity sites onto the surface of the magnetic spheres. Owing to the multivalency effect, the separation capacity of His-tagged proteins by the as-prepared Fe3O4@SiO2@polymer/Ni-NTA composites was four times as that by Fe3O4@SiO2/Ni-NTA, making them particularly promising for the magnetic separation of low-concentration His-tagged proteins. The magnentic polymer hybrid particles also exhibited excellent performance in the direct separation of His-tagged proteins from cells lysates. [ABSTRACT FROM AUTHOR]

Functionalized tetraarylporphyrin molecules have been widely used as ligands for the design of supramolecular coordination arrays. Even though a large number of porphyrin coordination compounds have been synthesized, three-dimensional networks are still less common. Here we report the hydrothermal synthesis and structure characterizations of four cadmium−porphyrin compounds based on meso-tetra(4-pyridyl)porphyrin (H 2TPyP). In these structures, both cadmium and porphyrin exhibit rich coordination chemistry. The porphyrin molecule displays four types of coordination modes in which each porphyrin molecule bonds to one, two, four, and five cadmium sites. The Cd 2+site shows equally diverse coordination modes and exists in five different coordination environments. The porphyrin molecules are connected through Cd 2+cations or Cd 3(SC 2H 2OH) 24+clusters into molecular (Cd−TPyP-1), two-dimensional (Cd−TPyP-4), and three-dimensional networks (Cd−H 2TPyP-2 and Cd−TPyP-3). Three-dimensional frameworks are of particular interest because they adopt interesting and rare framework topologies (cds and hms types). [ABSTRACT FROM AUTHOR]

A green gold-cluster, Au30S(StBu)18, was successfully prepared in high yield and crystallographically characterized. Each cluster consists of an Au22 core capped by a mixed layer of staple Au-thiolate units, bridging thiolates and a μ3-S2-. [ABSTRACT FROM AUTHOR]

A trace amount of metal carbonate, acetate or borate significantly boosts gold nanocatalysts in selective aerobic oxidation of alcohols under mild solvent-free conditions. [ABSTRACT FROM AUTHOR]

The article focuses on supported atomically dispersed palladium (Pd) catalysis for direct alkoxylation and allylic alkylation, emphasizing the catalyst's efficiency and unique mechanism. It discusses the utilization of atomically dispersed Pd on titanium dioxide (TiO2) nanosheets for direct allylic alkylation from allylic alcohols, highlighting the role of hydrogen bonding at the organic-inorganic interface in facilitating the reaction.

The article examines the structural and compositional diversity of metal-chelate dyes. The architecture of the metal-chelate dyes offers many possibilities in the controlled assembly of various low-charged nanuclaster. The metal-chelate dyes can induce the crystallization of various tetrahedral cluster.

The article focuses on a study related to Na5(In4S)(lnS4)3·6H4O, a zeolite-like structure with unusual SIn4 tetrahedra. Open framework materials have been widely studied for applications in a variety of technological areas such as gas storage and separation, catalysis, sorption, and ion exchange. Since 1989, open framework chalcogenides have attracted increasing attention because they are capable of integrating uniform porosity with semiconductivity and are promising candidates for applications ranging from shape-selective sensors to efficient visible-light photocatalysts.

Examines sulfide nanoclusters in cubic carbon nitride. Crystallography; Microporosity; Incorporation of divalent cations into indium sulfide clusters.

Discusses the synthesis of two open framework sulphides denoted as UCR-16 and 17 that have led to the creation of chalcogenide supertetrahedral clusters with unprecedented size and composition. Factor in the formation of the clusters; Properties of chalcogenide nanoclusters.

Catalytic hydrogenation of nitroaromatics is an environment‐benign strategy to produce industrially important aniline intermediates. Herein, we report that Fe(OH)x deposition on Pt nanocrystals to give Fe(OH)x/Pt, enables the selective hydrogenation of nitro groups into amino groups without hydrogenating other functional groups on the aromatic ring. The unique catalytic behavior is identified to be associated with the FeIII‐OH‐Pt interfaces. While H2 activation occurs on exposed Pt atoms to ensure the high activity, the high selectivity towards the production of substituted aniline originates from the FeIII‐OH‐Pt interfaces. In situ IR, X‐ray photoelectron spectroscopy (XPS), and isotope effect studies reveal that the Fe3+/Fe2+ redox couple facilitates the hydrodeoxygenation of the ‐NO2 group during hydrogenation catalysis. Benefitting from FeIII‐OH‐Pt interfaces, the Fe(OH)x/Pt catalysts exhibit high catalytic performance towards a broad range of substituted nitroarenes. [ABSTRACT FROM AUTHOR]

The article reports on a synthetic strategy for the preparation of ultrathin nanosheets as an excellent cost-effective catalyst for the electrochemical conversion of carbon dioxide and water into tunable syngas under low overpotentials. Topics discussed include fabrication, detailed structure and formation mechanism, stability, and catalytic performance in energy conversion of the unique copper-based ultrathin nanosheets.

Atomically dispersed noble metal catalysts often exhibit high catalytic performances, but the metal loading density must be kept low (usually below 0.5%) to avoid the formation of metal nanoparticles through sintering.We report a photochemical strategy tofabricate a stable atomically dispersed palladium-titanium oxide catalyst (Pd1/TiO2) on ethylene glycolate (EG)-stabilized ultrathin TiO2 nanosheets containing Pd up to 1.5%.The Pd1/TiO2 catalyst exhibited high catalytic activity in hydrogenation of C=C bonds, exceeding that of surface Pd atoms on commercial Pd catalysts by a factor of 9. No decay in the activity was observed for 20 cycles. More important, the Pd1/TiO2-EG system could activate H2 in a heterolytic pathway, leading to a catalytic enhancement in hydrogenation of aldehydes by a factor of more than 55. [ABSTRACT FROM AUTHOR]

Hybrid metal nanoparticles can allow separate reaction steps to occur in close proximity at different metal sites and accelerate catalysis. We synthesized iron-nickel hydroxide--platinum (transition metal-OH-Pt) nanoparticles with diameters below 5 nanometers and showed that they are highly efficient for carbon monoxide (CO) oxidation catalysis at room temperature. We characterized the composition and structure of the transition metal-OH-Pt interface and showed that Ni2+ plays a key role in stabilizing the interface against dehydration. Density functional theory and isotope-labeling experiments revealed that the OH groups at the Fe3+-OH-Pt interfaces readily react with CO adsorbed nearby to directly yield carbon dioxide (CO2) and simultaneously produce coordinatively unsaturated Fe sites for O2 activation. The oxide-supported PtFeNi nanocatalyst rapidly and fully removed CO from humid air without decay in activity for 1 month. [ABSTRACT FROM AUTHOR]

The article presents a study on oxidating benzyl alcohol-to-benzaldehyde. The study has used the newly developed mesoporous ternary metal oxide (K-Cu-TiO2) to activate the gas-phase oxidation of benzyl alcohol at a low temperature. The study has shown that using a high surface catalyst and a homogeneous distribution of multiple component structured into a matrix, the gas-phase oxidation of benzyl alcohol to benzaldehyde can be attained at a lower temperature.