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Ferdi Schuth - One of the best experts on this subject based on the ideXlab platform.

  • nitrogen doped Ordered Mesoporous Carbon supported bimetallic ptco nanoparticles for upgrading of biophenolics
    Angewandte Chemie, 2016
    Co-Authors: Guanghui Wang, Dong Gu, Bernd Spliethoff, Claudia Weidenthaler, Norbert Pfander, Annchristin Swertz, Hansjosef Bongard, Wolfgang Schmidt, Roberto Rinaldi, Ferdi Schuth
    Abstract:

    Hydrodeoxygenation (HDO) is an attractive route for the upgrading of bio-oils produced from lignocellulose. Current catalysts require harsh conditions to effect HDO, decreasing the process efficiency in terms of energy and Carbon balance. Herein we report a novel and facile method for synthesizing bimetallic PtCo nanoparticle catalysts (ca. 1.5 nm) highly dispersed in the framework of nitrogen-doped Ordered Mesoporous Carbon (NOMC) for this reaction. We demonstrate that NOMC with either 2D hexagonal (p6m) or 3D cubic (Im3‾ m) structure can be easily synthesized by simply adjusting the polymerization temperature. We also demonstrate that PtCo/NOMC (metal loading: Pt 9.90 wt %; Co 3.31 wt %) is a highly effective catalyst for HDO of phenolic compounds and "real-world" biomass-derived phenolic streams. In the presence of PtCo/NOMC, full deoxygenation of phenolic compounds and a biomass-derived phenolic stream is achieved under conditions of low severity.

  • aqueous synthesis of Ordered Mesoporous Carbon via self assembly catalyzed by amino acid
    Chemistry of Materials, 2008
    Co-Authors: Anhui Lu, Bernd Spliethoff, Ferdi Schuth
    Abstract:

    In this manuscript, we demonstrate a synthesis of Ordered Mesoporous Carbon via a self-assembly of resorcinol-formaldehyde polymer and surfactant F127 in aqueous phase in the presence of glutamic acid as the catalyst. It was found that the amounts of glutamic acid and surfactant F127 in the synthesis are important in determining the structural ordering of the resultant Mesoporous Carbons. The textural parameters of the obtained Ordered Mesoporous Carbon are tunable simply by varying the pyrolysis temperature. The process has the advantage of being a single step self-assembly approach and only involves the use of simple organic precursors and water.

  • molecular level dispersed pd clusters in the Carbon walls of Ordered Mesoporous Carbon as a highly selective alcohol oxidation catalyst
    Chemical Communications, 2007
    Co-Authors: Anhui Lu, Wencui Li, Ferdi Schuth
    Abstract:

    Ordered Mesoporous Carbon containing molecular-level dispersed Pd clusters in the Carbon walls can be synthesized by the nanocasting pathway, which shows high selectivity for the oxidation of alcohols to aldehydes.

  • facile template synthesis of Ordered Mesoporous Carbon with polypyrrole as Carbon precursor
    Chemistry of Materials, 2005
    Co-Authors: Chiamin Yang, Bernd Spliethoff, Claudia Weidenthaler, M Mamatha, Ferdi Schuth
    Abstract:

    A new and facile synthetic route of Ordered Mesoporous Carbon with polypyrrole as Carbon precursor has been developed. The Mesoporous silica host is first impregnated with ferric chloride, which serves as the oxidant for the vapor-phase oxidative polymerization of pyrrole vapor at room temperature. Such a stoichiometric reaction provides a rational control of loading with polypyrrole and also determines the amount of Carbon after subsequent pyrolysis in the host silica. Ordered Mesoporous Carbon is obtained after the dissolution of silica and iron species. The materials thus prepared have Ordered structure, large surface area, and pore volume. They are Ordered on the mesoscopic scale and show some graphitic order on the atomic scale.

Dingsheng Yuan - One of the best experts on this subject based on the ideXlab platform.

  • Facile fabrication of copper-supported Ordered Mesoporous Carbon for antibacterial behavior
    Materials Letters, 2010
    Co-Authors: Fengping Jiang, Dingsheng Yuan
    Abstract:

    Abstract Copper-supported Ordered Mesoporous Carbon (Cu/CMK-3) was prepared by impregnating Ordered Mesoporous Carbon (CMK-3) with CuCl 2 aqueous solution. CMK-3 was served as a carrier for the continuous immobilization of Cu. The supported copper was observed to be the bivalence state, indicating that the Cu 2+ ion was not reduced into cuprous species or metallic copper in the CMK-3. The BET surface area and pore volume of Cu/CMK-3 were 728 m 2 /g and 0.95 cm 3 /g, respectively. The antibacterial activities of Cu/CMK-3 were tested by means of minimal inhibitory concentration (MIC) and viable cell counting method. The results show that Cu/CMK-3 presents a good antibacterial performance against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ), which indicates its potential applications as antibacterial material for microbiocides.

  • Facile fabrication of copper-supported Ordered Mesoporous Carbon for antibacterial behavior
    Materials Letters, 2010
    Co-Authors: Sanxiang Tan, Wujun Zou, Fengping Jiang, Shaozao Tan, Yingliang Liu, Dingsheng Yuan
    Abstract:

    Copper-supported Ordered Mesoporous Carbon (Cu/CMK-3) was prepared by impregnating Ordered Mesoporous Carbon (CMK-3) with CuCl2 aqueous solution. CMK-3 was served as a carrier for the continuous immobilization of Cu. The supported copper was observed to be the bivalence state, indicating that the Cu2+ ion was not reduced into cuprous species or metallic copper in the CMK-3. The BET surface area and pore volume of Cu/CMK-3 were 728 m 2/g and 0.95 cm3/g, respectively. The antibacterial activities of Cu/CMK-3 were tested by means of minimal inhibitory concentration (MIC) and viable cell counting method. The results show that Cu/CMK-3 presents a good antibacterial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which indicates its potential applications as antibacterial material for microbiocides. © 2010 Elsevier B.V. All rights reserved.

  • bi2o3 deposited on highly Ordered Mesoporous Carbon for supercapacitors
    Electrochemistry Communications, 2009
    Co-Authors: Dingsheng Yuan, Yi Wang, Jianghua Zeng, Noel Kristian, Xin Wang
    Abstract:

    Abstract A simple route has been employed to prepare nanosized Bi 2 O 3 deposited on highly Ordered Mesoporous Carbon. The electrochemical measurements reveal that, by loading only 10% Bi 2 O 3 on the Mesoporous Carbon, the specific capacitance of the composite is improved by 62%, with the maximum value reaching 232 F g −1 at a sweep rate of 5 mV s −1 . The specific capacitance of Bi 2 O 3 is calculated and reaches 1305 F g −1 at 1 mV s −1 . It is found that the mass transfer in the framework of the crystalline oxide is still difficult in spite of its nanosize, as evidenced by the decline of the specific capacitance of the Bi 2 O 3 with the increase of the sweep rate. The cyclic life of composite materials is also measured and the capacitance only declines 21% after 1000 cycles.

Ryong Ryoo - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis of Ordered Mesoporous Carbon molecular sieves CMK-1
    Microporous and Mesoporous Materials, 2020
    Co-Authors: Ryong Ryoo
    Abstract:

    Highly Ordered Mesoporous Carbon molecular sieves designated as CMK-1 were synthesized using Mesoporous MCM-48 silica with various pore diameters as templates. sucrose as a Carbon source and sulfuric acid as the Carbonization catalyst. The effect of the sucrose-to-sulfuric acid ratio on the structure of the resultant Carbon, the effect of the pyrolysis temperature, and the optimum amounts of sucrose for MCM-48 with various pore diameters have been investigated. These results show that the synthesis method can be accurately controlled to obtain the highly Ordered Mesoporous Carbon molecular sieves in a large scale.close12411

  • synthesis of Ordered Mesoporous Carbon molecular sieves cmk 1
    Microporous and Mesoporous Materials, 2001
    Co-Authors: Ryong Ryoo
    Abstract:

    Highly Ordered Mesoporous Carbon molecular sieves designated as CMK-1 were synthesized using Mesoporous MCM-48 silica with various pore diameters as templates, sucrose as a Carbon source and sulfuric acid as the Carbonization catalyst. The effect of the sucrose-to-sulfuric acid ratio on the structure of the resultant Carbon, the effect of the pyrolysis temperature, and the optimum amounts of sucrose for MCM-48 with various pore diameters have been investigated. These results show that the synthesis method can be accurately controlled to obtain the highly Ordered Mesoporous Carbon molecular sieves in a large scale.

Jianping He - One of the best experts on this subject based on the ideXlab platform.

  • In situ palladium/nitrogen-doped Ordered Mesoporous Carbon hybrids as highly active and durable electrocatalysts for oxygen reduction reaction
    Journal of Porous Materials, 2018
    Co-Authors: Tao Wang, Li Song, Hao Gong, Linghui Li, Jianping He
    Abstract:

    N-doped Ordered Mesoporous Carbon–Pd hybrids are successfully fabricated through a facile synchronous-assembly method. The metallic Pd nanoparticles with uniform diameter around 15 nm were inserted into the Ordered Mesoporous Carbon matrix, while the nitrogen element is also successfully doped into Ordered Mesoporous Carbon. The composite can not only facilitate electrolyte infiltration but also ensure fast electronic transmission for their high surface area and good electroconductivity. By adjusting the amount of doped N to 3 wt%, the open-framework structure of the Ordered Mesoporous Carbon can be maintained and the composite exhibits excellent electrocatalytic activity of oxygen reduction reaction (ORR). The catalyst shows the onset potential of − 0.045 V (vs. SCE) in 0.1 M KOH, which is comparable to commercial Pt/C. Moreover, the N-doped Ordered Mesoporous Carbon–Pd hybrids show outstanding methanol tolerance in alkaline media. The significant performance towards ORR is attributed to the uniform Pd nanoparticles and successful doped nitrogen along with the special open-framework structure.

  • Constructing a multicomponent Ordered Mesoporous Carbon for improved electrochemical performance induced by in-situ doping phosphorus
    Carbon, 2016
    Co-Authors: Tao Wang, Hao Gong, Jianqing Zhao, Jing Tang, Jianping He
    Abstract:

    Abstract The functional phosphorus-containing Ordered Mesoporous Carbon (POMC) films are facilely fabricated through in-situ evaporation-induced self-assembly strategy using phosphorus-modified resol as the Carbon precursor and triblock copolymer as the soft template agent. The in-situ introduction of phosphorus not only promotes pyrolysis reaction of Carbon source but also benefits for aromatization of Carbon via polycondensation reaction, and thus significantly enhances graphitization of Ordered Mesoporous Carbon (OMC) materials even prepared at a very low temperature (500 °C) together with desirable porosity and conductivity. As a result, POMC film shows improved corrosion resistance in comparison with pristine OMC film, due to its excellent hydrophobicity and high graphitization. Moreover, benefiting from the Ordered Mesoporous structure, enhanced graphitization, doping of phosphorus, and high dispersion of Pt nanoparticles, the designed POMC composite can also be acted as a Pt catalyst support, resulting in much higher electrocatalytic activities for both hydrogen oxidation and methanol oxidation than that of OMC film. This work offers an effective approach to enhance relative performance of Ordered Mesoporous Carbon materials for device applications.

  • In-situ Preparation of Pd Incorporated Ordered Mesoporous Carbon as Efficient Electrocatalyst for Oxygen Reduction Reaction
    Electrochimica Acta, 2016
    Co-Authors: Li Song, Tao Wang, Jianping He
    Abstract:

    Abstract We develop a facile method for the synthesis of size-controlled nano-crystaline palladium incorporated into Ordered Mesoporous Carbon (OMC) as oxygen reduction reaction (ORR) electrocatalyst, applied in the cathode of fuel cell and metal-air battery. The catalyst with 18 wt.% Pd in Ordered Mesoporous Carbon, pyrolyzed at 900 °C shows excellent catalytic performance for ORR. The onset and half-wave potentials are 0.963 V and 0.872 V (vs. RHE) in 0.1 M KOH, respectively, which are comparable to those of commercial 30 wt.% Pt/C, 0.975 V and 0.854 V (vs. RHE). The catalyst with 12 wt.% Pd in Ordered Mesoporous Carbon shows largest limiting current density when the current is normalized by the mass of noble metal. The efficient utilization of active Pd in the Mesoporous Carbon framework endows the catalyst an almost direct four-electron reduction pathway. The transferred electron number of 12Pd-OMC-900 is calculated to be 4.14 at 0.4 V (vs. RHE). Its excellent ORR activity should be ascribed to the optimized balance between active sites (Pd nanoparticles) density and capability for mass and charge transport. In addition, the protection for active moieties in the OMC frameworks contributes to its superior durability compared with Pt/C.

  • The oriented growth of tungsten oxide in Ordered Mesoporous Carbon and their electrochemical performance.
    Nanoscale, 2014
    Co-Authors: Tao Wang, Jianhua Zhou, Jing Tang, Jianping He
    Abstract:

    Electrocatalysts for hydrogen oxidation and methanol oxidation are the heart of the proton exchange membrane fuel cell. In spite of tremendous efforts, developing low-cost anodic electrocatalysts with high catalytic activity and corrosion resistance is still a great challenge. Here, we report a nanocomposite consisting of oriented WO3 nanorods grown in Ordered Mesoporous Carbon as a high-performance functional catalyst carrier for proton exchange membrane fuel cells. As a result of the catalytic graphitization effect of tungsten compounds, the degree of graphitization and conductivity of Mesoporous Carbon film were improved even at a low temperature. Furthermore, compared with Ordered Mesoporous Carbon, Ordered Mesoporous C–WO3 nanocomposites possess favorable hydrophilicity, excellent corrosion resistance and notable electrocatalytic activities. The unusual electrocatalytic activities arise from the ideal physical properties of the carrier and synergetic catalysis between Pt and WO3.

  • synthesis and electrochemical characterization of n doped partially graphitized Ordered Mesoporous Carbon co composite
    Journal of Physical Chemistry C, 2013
    Co-Authors: Jing Tang, Tao Wang, Jianping He
    Abstract:

    N-doped Ordered Mesoporous Carbon–Co composites (Co-N-OMC) with 2D hexagonal structure, uniform pore size (4.4 nm), high surface area (550 m2 g–1), and medium pore volume (0.61 cm3 g–1) were successfully fabricated through facile one-step template method. We employed resol as the Carbon precursor, triblock copolymer as the template agent, and cobaltous acetate and urea as additives. XPS analysis revealed that nitrogen was successfully doped in Ordered Mesoporous Carbon and existed in the form of pyridine-like and quaternary-N nitrogen atoms. More importantly, metallic Co nanoparticles with uniform diameter around 15 nm highly dispersed in Carbon matrix without adding any dispersion agent, which was probably due to the confinement effect of Mesoporous structure. It was unambiguously demonstrated by HRTEM analysis that there were layered graphitic sheets present around Co particles, resulting from in situ catalytic graphitization of amorphrous Carbon by Co species. Pt catalyst deposited on Co-N-OMC composit...

Dongyuan Zhao - One of the best experts on this subject based on the ideXlab platform.

  • Ordered Mesoporous Carbon sulfur nanocomposite of high performances as cathode for lithium sulfur battery
    Electrochimica Acta, 2011
    Co-Authors: Shuru Chen, Dongyuan Zhao, Yunpu Zhai, Guiliang Xu, Yanxia Jiang, Juntao Li, Ling Huang, Shigang Sun
    Abstract:

    Abstract Ordered Mesoporous Carbon/sulfur (OMC/S) nanocomposites with hierarchically structured sulfur loading, ranging from 50 to 75 wt%, were synthesized via a simple melt-diffusion strategy. The OMC with a BET surface area of 2102 m 2  g −1 , a pore volume of 2.0 cm 3  g −1 and unique bimodal Mesoporous (5.6/2.3 nm) structure, was prepared from a triconstituent co-assembly method. The resulting OMC/S nanocomposite material served as cathode of rechargeable lithium–sulfur (Li–S) battery. It has been tested that the novel OMC/S cathode can deliver a superior reversible capacity and cyclability. In particular, the nanocomposite with a loading of 60 wt% sulfur (OMC/S-60) presents the highest sulfur utilization ca. 70%, an excellent high rate capability ca. 6 C and a good cycling stability for up to 400 full charge–discharge cycles. The exceptional electrochemical performances are exclusively attributed to the large internal surface area and high porosity of the Ordered Mesoporous Carbon, which favorites both electron and Li-ion transportations.

  • A low-concentration hydrothermal synthesis of biocompatible Ordered Mesoporous Carbon nanospheres with tunable and uniform size
    Angewandte Chemie - International Edition, 2010
    Co-Authors: Yin Fang, Renchao Che, Ying Zou, Dong Gu, Yonghui Deng, Zhangxiong Wu, Fuyou Li, Bo Tu, Dongyuan Zhao
    Abstract:

    Mesoporous Carbon nanoparticles with uniform spherical morphology were fabricated through a low-concentration hydrothermal synthesis route. The diameters can be tuned from 20 to 140nm by varying the reagent concentration. The highly Ordered Mesoporous Carbon nanospheres with high surface area and large pore volume show low cytotoxicity and can easily penetrate into living cells.

  • electrochemical properties of an Ordered Mesoporous Carbon prepared by direct tri constituent co assembly
    Carbon, 2007
    Co-Authors: Huiqiao Li, Dongyuan Zhao
    Abstract:

    Abstract An Ordered Mesoporous Carbon with a high surface area of 2390 m 2 /g and a large pore size of 6.7 nm was synthesized through an organic–inorganic-surfactant tri-constituent co-assembly method which used resols as the Carbon precursor, silicate oligomers as the inorganic precursor and triblock copolymer as the soft template. The electrochemical properties of this Carbon were evaluated as an electrode material for electrochemical double layer capacitor and lithium-ion battery. It shows rectangular-shaped cyclic voltammetry curves over a wide range of scan rates even up to 200 mV/s between 0 and 3 V, with a large capacitance of 112 F/g in nonaqueous electrolyte. As a negative electrode material for lithium-ion battery, it delivers a reversible specific capacity as high as 1048 mAh/g and a good cycling ability with capacity retention of 500 mAh/g over 50 cycles.

  • Morphological control of highly Ordered Mesoporous Carbon
    Studies in Surface Science and Catalysis, 2007
    Co-Authors: Chengzhong Yu, Bozhi Tian, Fuqiang Zhang, G. D. Stucky, Dongyuan Zhao
    Abstract:

    Highly Ordered Mesoporous Carbon materials with fiber-like, plate-like, rod-like and donut-like morphologies have been synthesized by using Mesoporous silica as the templates.

  • a simple melt impregnation method to synthesize Ordered Mesoporous Carbon and Carbon nanofiber bundles with graphitized structure from pitches
    Journal of Physical Chemistry B, 2004
    Co-Authors: Haifeng Yang, Bo Tu, Fuqiang Zhang, Renyuan Zhang, Yan Meng, Mei Li, Dongyuan Zhao
    Abstract:

    In this paper, we report a simple melt impregnation method by using cheap mesophase pitches (MPs) as Carbon precursors to prepare Ordered Mesoporous Carbon with Ordered graphitized pore walls at low temperature. This facile procedure includes melting MPs at 140 °C and impregnation of the melt into hexagonal or bicontinuous cubic Mesoporous silica templates. After the removal of silica templates by HF solution, Ordered Mesoporous Carbon materials with replica structures of 2-D hexagonal p6mm or cubic Ia3d symmetry were derived. The pore walls of the hexagonal Mesoporous Carbon products are composed of graphitized domains with the (002) crystallographic plane of the graphite perpendicular to the long axis of the Carbon nanorods. Theoretical computations show that negatively charged O atoms of Si−OH and Si−O−Si from the surface of Mesoporous silica channels can interact with the positive charged H atoms of the MPs, which makes the stacking units incorporate into the pores with the (002) plane vertical to th...