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Phys Chem Chem Phys ; 19(33): 22596, 2017 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-28796268


Correction for 'Zeolitic imidazolate framework (ZIF-8) derived nanoporous carbon: the effect of carbonization temperature on the supercapacitor performance in an aqueous electrolyte' by Christine Young et al., Phys. Chem. Chem. Phys., 2016, 18, 29308-29315.

Chem Asian J ; 12(3): 283-288, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27943602


The capture and storage of CO2 have been suggested as an effective strategy to reduce the global emissions of greenhouse gases. Hence, in recent years, many studies have been carried out to develop highly efficient materials for capturing CO2 . Until today, different types of porous materials, such as zeolites, porous carbons, N/B-doped porous carbons or metal-organic frameworks (MOFs), have been studied for CO2 capture. Herein, the CO2 capture performance of new hybrid materials, graphene-organic frameworks (GOFs) is described. The GOFs were synthesized under mild conditions through a solvothermal process using graphene oxide (GO) as a starting material and benzene 1,4-diboronic acid as an organic linker. Interestingly, the obtained GOF shows a high surface area (506 m2 g-1 ) which is around 11 times higher than that of GO (46 m2 g-1 ), indicating that the organic modification on the GO surface is an effective way of preparing a porous structure using GO. Our synthetic approach is quite simple, facile, and fast, compared with many other approaches reported previously. The synthesized GOF exhibits a very large CO2 capacity of 4.95 mmol g-1 at 298 K (1 bar), which is higher those of other porous materials or carbon-based materials, along with an excellent CO2 /N2 selectivity of 48.8.

Chemistry ; 22(50): 18259-18264, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27797428


Cobalt sulfide/sulfur doped carbon composites (Co9 S8 /S-C) were synthesized by calcining a rationally designed sulfur-containing cobalt coordination complex in an inert atmosphere. From the detailed transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses, the electrocatalytically active Co9 S8 nanoparticles were clearly obtained and combined with the thin sulfur doped carbon layers. Electrochemical data showed that Co9 S8 /S-C had a good activity and long-term stability in catalyzing oxygen evolution reaction in alkaline electrolyte, even better than the traditional RuO2 electrocatalyst. The excellent electrocatalytic activity of Co9 S8 /S-C was mainly attributed to the synergistic effect between the Co9 S8 catalyst which contributed to the oxygen evolution reaction and the sulfur doped carbon layer which facilitated the adsorption of reactants, prevented the Co9 S8 particles from aggregating and served as the electrically conductive binder between each component.

Phys Chem Chem Phys ; 18(42): 29308-29315, 2016 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-27731874


Nanoporous carbon materials are a versatile source of carbons that would be useful in applications ranging from electronics to electrochemical energy storage. Here, we focus on nanoporous carbon materials prepared by direct carbonization of zeolitic imidazolate frameworks (ZIF-8) towards supercapacitor applications. Several types of nanoporous carbons have been prepared by varying the applied carbonization temperature. The symmetric devices assembled using nanoporous carbon electrodes were tested for their optimal performance in the electrolyte of sulfuric acid solution. We demonstrate the effects of various factors (e.g., surface area, nitrogen content, degree of graphitization, and relative percentage of micropores) on the performance.

Chemistry ; 22(42): 15042-15048, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27594526


The synthesis of a novel family of cyano-bridged trimetallic coordination polymers (CPs) with various compositions and shapes has been reported by changing the compositional ratios of Fe, Co, and Ni species in the reaction system. In order to efficiently control the nucleation rate and the crystal growth, trisodium citrate dihydrate plays an important role as a chelating agent. After the obtained cyano-bridged trimetallic CPs undergo thermal treatment in air at three different temperatures (250, 350, and 450 °C), nanoporous spinel metal oxides are successfully obtained. Interestingly, the obtained nanoporous metal oxides are composed of small crstalline grains, and the grains are oriented in the same direction, realizing pseudo-single crystals with nanopores. The resultant nanoporous spinel oxides feature interesting magnetic properties. Cyano-bridged multimetallic CPs with various sizes and shapes can provide a pathway toward functional nanoporous metal oxides that are not attainable from simple cyano-bridged CPs containing single metal ions.

Beilstein J Nanotechnol ; 2: 809-13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22259764


The effect of depositing FeO nanoparticles with a diameter of 10 nm onto the surface of MgB(2) thin films on the critical current density was studied in comparison with the case of uncoated MgB(2) thin films. We calculated the superconducting critical current densities (J(c)) from the magnetization hysteresis (M-H) curves for both sets of samples and found that the J(c) value of FeO-coated films is higher at all fields and temperatures than the J(c) value for uncoated films, and that it decreases to ~10(5) A/cm(2) at B = 1 T and T = 20 K and remains approximately constant at higher fields up to 7 T.