Nanoporous carbon nanoparticles with high graphitic nitrogen amounts were synthesized and used as a metal free catalyst for effective HMF-to-FDCA conversion.

We demonstrate a cellulose-templating method for synthesizing a hierarchically porous carbon electrode that is capable of high-performance capacitive deionization (CDI). Hierarchically porous carbons (denoted as HPC-X, X = 500− 900 °C) of an exceptionally high surface area up to 2535 m 2 g −1 and wide-range pore size distribution (macro-, meso-, and micropores) were obtained via the pyrolysis of macroporous cellulose fibrous-templated resorcinol-formaldehyde-triaminopyrimidine (RF-TPF) polymers. The improved electrosorption performance of HPC-800 electrode can be ascribed to the enhanced specific surface area, favorable hierarchical structure, and excellent capacitive electric double layer behaviors.

A de novo synthesis of gold nanoparticles embedded, nitrogen doped nanoporous carbon nanoparticles (Au@NC) was synthesized in this work. The chloroauroic acid was encapsulated inside zeolitic imidazolate framework-8 (ZIF-8) nanoparticles during the synthesis and later reduced into gold nanoparticles. The as-synthesized gold nanoparticles embedded ZIF-8 (Au@ZIF-8) was then carbonized into Au@NC to enhance the stability of the nanoporous support. The results showed that Au@NC exhibited a porous structure containing 3wt% of gold. 2-Methylimidazole provided abundant nitrogen (19wt%) on the carbon matrix, resulting in hydrophilic and positive charge surface that is useful for the reduction of 4-nitrophenol. The results of the catalytic reaction indicated that the synthesized Au@NC could act as an effective catalyst with turnover frequency (TOF) of 1185 g -1 s -1 , which is higher than that of conventional naked Au nanoparticles (TOF of 339 g -1 s -1 ) and Au nanoparticles on activated carbon (TOF of 89 g -1 s -1 ). We propose that the enhanced performance of the Au@NC resulted from the homogeneous distribution of Au nanoparticles along with the hydrophilic and positive charge surface of nitrogen-doped carbon surface.Catalysis has been involved at the core of nearly all chemical protocols from scientific research to industrial applications. In general, catalysis could be divided into homogeneous and heterogeneous catalysis. Both of homogenous and heterogeneous catalysts have their own advantages and drawbacks. [1] Some homogeneous catalysts have been tried to converted into hetrogeneous catalysts for easy recycling and other advantages. [2] In recent years, not only organic functional groups but also organometallic compounds and metallic nanoparticles have been decorated on different supports to change homogeneous catalyst into heterogeneous catalyst. [3] Mesoporous silica and zeolite are common supports for metal nanoparticles and organic functional groups since silica displays excellent chemical and thermal stability, extreme accessibility, high surface area, and easy functionalization. [4] As an example of such a recent development, Castro and co-workers functionalized ionic liquids on MCM-41 type mesoporous silica, which exhibited enhanced dodecene conversion efficacy as compared to that of the corresponding pure ionic liquids (i.e., 95% vs. 5%). [5] In addition to silica-based supports, metal oxides such as titania, magnesium oxide, and cerium oxide have also been utilized as effective supports for loading metal nanoparticles. [6] Metal oxides are utilized due to the capability for oxygen vacancies in the oxides to reduce the activation energy of catalytic reactions. [7] Other than silica and metal oxides, catalytic supports of carbon-based materials including activated carbon, mesoporous carbon, and graphite have also been widely used owing to their high stability towards acidic or basic environments. [8] Moreover, another advantage of carbon-based supports is the possible interactions between the catalytically ...

In this work, the impacts of varying surface modification, matrix parameters, and fabrication conditions on the performance of optically printed (0-3) piezoelectric polymer nanocomposites are examined. For example, we find that a 75% reduction in nanoparticle edge-length boosted the piezoelectric coefficient (d) by over 100%. By optimizing the composition and fabrication conditions, 10% by mass loading barium titanate nanocomposites are able to yield d values of ∼80 pC/N compared to <5 pC/N when parameters are not optimized. With a more complete understanding of how to enhance the performance of (0-3) piezoelectric polymer nanocomposites, these materials should find use in a wide range of applications.

This study illustrates the directed self-assembly of mesoporous TiO2 with magnetic properties due to its colloidal crystal structure with Fe3O4. The Fe3O4 nanoparticles were synthesized using co-precipitation techniques to a size of 28.2 nm and a magnetic saturation of 66.9 emu g(-1). Meanwhile, mesoporous titania nanoparticles (MTNs) with a particle diameter of 373 nm, a specific surface area of 236.3 m(2) g(-1), and a pore size of 2.8 nm were prepared by controlling the rate of hydrolysis. Magnetic colloidal crystals (a diameter of 10.2 μm) were formed by the aggregation of Fe3O4 and MTNs caused by the interface phenomena during solvent evaporation in emulsion. Even the anatase octahedrite produced from the colloidal crystal after a hydrothermal reaction retained a magnetic saturation of 2.8 emu g(-1). This study also investigates the photodegradation activity of our synthesized material as a photocatalyst, while utilizing its capability for magnetic separation to prove its usefulness in catalyst recycling.

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Iron pyrite has long been an attractive material for environmental and energy applications, but is hampered by a lack of control over morphology and purity. Hollow porous iron pyrite nanoparticles were synthesized by a direct sulfurization of iron oxide derived from Prussian blue. The high efficiencies of these hollow porous iron pyrite nanoparticles as effective dye-sensitized solar cell counter electrodes were demonstrated, with an efficiency of 7.31 %.

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