Publications (4)16.74 Total impact
Article: Ordered mesoporous polymers and homologous carbon frameworks: amphiphilic surfactant templating and direct transformation.Angewandte Chemie International Edition 12/2005; 44(43):7053-9. · 13.45 Impact Factor
Article: Nitrogen-containing carbon spheres with very large uniform mesopores: The superior electrode materials for EDLC in organic electrolyte[show abstract] [hide abstract]
ABSTRACT: We reported the electrochemical studies on mesoporous carbon spheres (MCS) enriched in nitrogen on frameworks serving as an electrode for electric double layer capacitor (EDLC) in an organic electrolyte. The preparation of the carbon spheres is involved in a facile polymerization-induced colloid aggregation method by using melamine-formaldehyde resin (MF) as the carbon precursor, and commercial fumed silica (Aerosil-200) as a hard template. After the carbonization of as-formed resin-template composites at 1000 °C under a nitrogen atmosphere, and the removal of silica template by HF treatment, monodisperse MCS with diameter size of ∼1.2 μm, high specific surface area (up to 1460 m2/g) and uniform pore size as large as 31 nm can be obtained. The MCS product presents a high specific capacitance as 159 F/g at 0.5 A/g. The high specific capacitance of the MCS is believed to be associated with its suitable nitrogen content that can afford pseudocapacitance as well as the high specific surface area. Furthermore, the specific capacitance of MCS can remain 130 F/g at high current density of 20 A/g. Our results show that the moderate nitrogen content can enhance the surface wettability and reduce the resistance, the large pore size can accelerate the diffusion process for the ions solvated with big organic solvent molecules in the pores. In view of the facts that precursors used in this simple process are commercially available low-cost chemicals, researches on the synthesis of such MCS materials templated by silica nanoparticles may not only be theoretically important, but also provide more options for economical and large-scale productions of mesoporous carbon materials with desired nanostructures, which might find practical applications in the fields of EDLC with high power performance.Carbon.
Article: Synthesis and phase behaviors of bicontinuous cubic mesoporous silica from triblock copolymer mixed anionic surfactant[show abstract] [hide abstract]
ABSTRACT: Highly ordered mesoporous silicas with bicontinuous cubic structure (space group of ) have been synthesized via a sol–gel route by the condensation of tetraethyl orthosilicate (TEOS) in a mixed surfactant system, poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) triblock copolymer P123 (EO20PO70EO20) mixed with sodium dodecylbenzene sulfonate (SDBS). Small-angle powder XRD, TEM, dynamic light scattering (DLS), and nitrogen adsorption were utilized to determine the phase diagram and illustrate the factors that define the phase boundary lines. The results show that the bicontinuous cubic mesophase can be reproducibly obtained in a large phase area in the acid concentration–temperature phase diagram, which is induced by anionic surfactant SDBS. A mesophase transformation from 2-D hexagonal p6mm to cubic can be easily observed as the decrease of acid concentration and increase of temperature. The decrease of hydrophilic–hydrophobic ratio (VH/VL) of the mixed surfactant micelles favors the formation of the mesophase. Furthermore, the mesophase formed with 3.0 M HCl at 45 °C was found to possess a microtubule morphology with the diameter of 1–3 μm, the wall thicknesses of about 0.5 μm, and length up to hundreds of micrometers.Microporous and Mesoporous Materials 105:34-40. · 3.29 Impact Factor
Article: Nitrogen enriched mesoporous carbon spheres obtained by a facile method and its application for electrochemical capacitor[show abstract] [hide abstract]
ABSTRACT: A kind of mesoporous carbon spheres (MCS) containing in-frame incorporated nitrogen has been prepared by a facile polymerization-induced colloid aggregation method. As the electrode material for electric double layer capacitor (EDLC) in 5 mol/L H2SO4, the MCS products present excellent specific capacitance as 211 F/g much larger than that of the most popularly applied activated carbon at a high discharge current density of 1 A/g. Its specific capacitance can still remain 200 F/g at 20 A/g. The superior electrochemical performance of MCS is associated with the following characteristics: high specific surface area (∼1330 m2/g) contributed mainly by the mesopores, uniform pore size as large as 29 nm and moderate content of nitrogen (10 wt%), which are the requirements for ideal supercapacitors.Electrochemistry Communications.