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The present study describes a methodology to heterogenize metallic Co nanoparticles (NPs) on hollow Fe3O4 nanospheres, surface-functionalized with a porous covalent triazine framework, leading to a magnetically separable catalyst that exhibits efficient catalytic activity in hydrogenation, ligand-free Buchwald-Hartwig N-arylation, and oxidation reactions. Here, the presence of a nitrogen-enriched porous structure is expected to provide potential interactions with active centers through coordination (M←N), enable the isolation of the entrapped catalytically active Co NPs, and prevent the possibility of sintering during catalytic reactions, resulting in structurally stable catalytic sites, which makes them recyclable without any loss in activity. [ABSTRACT FROM AUTHOR]

Thiazoline functionalized periodic mesoporous organosilica (TPMO) supported palladium nanoparticles (Pd‐TPMO) were fabricated through a co‐condensation approach and successive incorporation of palladium nanoparticles using a double‐solvent technique. The TPMO and Pd‐TPMO were characterized through 29Si MAS NMR, FTIR, SAXS, XPS, FESEM, TEM and N2 adsorption‐desorption, which revealed the morphological and physicochemical properties of the materials. The catalytic performance of Pd‐TPMO was evaluated for hydrogenation of industrially important compounds and Csp2−Csp2 bond‐formation reactions. The Pd‐TPMO mediated catalytic reactions were found to be effective in producing the corresponding products with excellent yields and selectivity. The size and stability of palladium nanoparticles within the confined organosilica framework promotes excellent activity and recyclability of the catalyst without a significant loss in the yields for hydrogenation and Csp2−Csp2 bond‐formation reactions. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate that a bioinspired assembly of silica nanoparticles with polyamines as structure-directing agents similar to that known for the biosilicification of diatoms can pave the way for the efficient encapsulation of sulfonated copper-phthalocyanine in a hybrid microcapsule structure, in which the organic component provides a capable environment for its catalytic activity in epoxidation reactions and the nanoassembled structure imparts stability. [ABSTRACT FROM AUTHOR]

Tuning the physical and chemical interaction between metal–metal′ (M−M′) and metal–support is an ideal way to realize enhanced catalytic activity of metal nanoparticles (NPs). As a proof of concept, herein we report the fabrication of nickel‐gold (Ni−Au) alloy nanoparticles attached to N‐doped nanoporous carbon (NPC) intervened with MgO (Ni73Au27@MgO‐NPC), achieved through the impregnation of metal precursors into Schiff‐base network polymer (SNP) framework along with Mg(OH)2 and pyrolysis at 800 °C in N2 atmosphere. With high stability and heterogeneity, the nickel rich Ni73Au27@MgO‐NPC exhibited higher catalytic activities with turnover frequencies of 29,272 h−1 (hydrogenation of p‐nitrophenol), 93,843 h−1 (degradation of methyl orange), and 2,218 h−1 (epoxidation of stilbene), compared to commercial 10 wt % Pd/C. Enhanced catalytic activity is correlated to the synchronized electron density enhancement in Au, by Ni and MgO/N‐rich nanoporous carbon heterostructures, as evident from detailed X‐ray photoelectron spectroscopic studies. [ABSTRACT FROM AUTHOR]

Isolated chemical reactors were fabricated by integrating catalytically active sites (Pd) with magnetic functionality (Fe3O4) along with carbon while preserving the constituents functional properties to realize the structure-property relationship of Pd by comparing the catalytic activity of spherical Pd NPs with cubical Pd NPs for cyanation in aryl halides using K4[Fe(CN)6] as a green cyanating agent to yield corresponding nitriles. The superior catalytic reactivity of the cubical Pd NPs is attributed to the larger number of {100} surface facets. The TEM images of reused catalyst shows the change in structure from cubical to spherical nanoparticles, attributed to the efficient leaching susceptibility of Pd {100} surface facets. The cubical Pd NPs on carbon@Fe3O4 is attractive in view of its high catalytic efficiency, easy synthesis, magnetic separability, environmental friendliness, high stability, gram scale applicability, and reusability.

In analogy to the role of long-chain polyamines in biosilicification, poly-L-lysine facilitates the assembly of nanocomponents to design multifunctional microcapsule structures. The method is demonstrated by the fabrication of a magnetically separable catalyst that accommodates Pd nanoparticles (NPs) as active catalyst, Fe3O4 NPs as magnetic component for easy recovery of the catalyst, and silica NPs to impart stability and selectivity to the catalyst. In addition, polyamines embedded inside the microcapsule prevent the agglomeration of Pd NPs and thus result in efficient catalytic activity in hydrogenation reactions, and the hydrophilic silica surface results in selectivity in reactions depending on the polarity of substrates., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Herein, we demonstrate that a bioinspired assembly of silica nanoparticles with polyamines as structure-directing agents similar to that known for the biosilicification of diatoms can pave the way for the efficient encapsulation of sulfonated copper-phthalocyanine in a hybrid microcapsule structure, in which the organic component provides a capable environment for its catalytic activity in epoxidation reactions and the nanoassembled structure imparts stability., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highly photoluminescent carbon nanodots (CNDs) were synthesized for the first time from metal-organic framework (MOF, ZIF-8) nanoparticles. Coupled with fluorescence and non-toxic characteristics, these carbon nanodots could potentially be used in biosafe color patterning., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)