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Zhongshan, China

He X.,Anhui University of Technology | Geng Y.,Anhui University of Technology | Qiu J.,Carbon Research Laboratory | Zheng M.,Anhui University of Technology | And 2 more authors.
Carbon | Year: 2010

Activated carbons (ACs) were prepared by microwave-assisted heat treatment of petroleum coke with KOH as activation agent, and characterized by infrared spectroscopy and nitrogen adsorption technique with the aim of studying the effect of activation time on the properties of ACs for electrodes in electric double layer capacitors (EDLCs). The electrochemical properties of AC electrodes in EDLCs were studied by cyclic voltammetry, constant current charge-discharge and electrochemical impedance spectroscopy. The results show that the specific surface area (SBET) and total pore volume of ACs goes through a maximum as the activation time increases. At 35 min of the activation time, the as-made AC (denoted as AC-35) has a SBET of 2312 m2/g. With AC-35 as the electrode, its specific capacitance in EDLC at a current density of 50 mA/g can reach 342.8 F/g, and remains at 245.6 F/g even after 800 cycles while the energy density of the capacitor remains at 8.0 Wh/kg. The results have demonstrated that the microwave-assisted heat treatment is an efficient approach to the preparation of ACs with high performance for EDLCs. © 2010 Elsevier Ltd. All rights reserved. Source

Wu T.,Carbon Research Laboratory
Advanced Engineering Materials | Year: 2015

A novel self-sufficient self-healing system for metal protection is demonstrated in this work. The system is sustainable and can provide effective and durative protection for metal through autonomously healing the protective layer on metal surface while without adding any additional consumable reagents or external powers. As the system is fabricated on the basis of stable oxygen reduction reaction catalyst, the self-healing process can be repeated many times. Furthermore, the combination of catalyst-induced repeatable self-healing of metal passivation and serviceability of polymers makes this system ideal for intelligent metal protection. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Wang H.,Shaanxi Normal University | Zhi L.,Shaanxi Normal University | Liu K.,Shaanxi Normal University | Dang L.,Shaanxi Normal University | And 4 more authors.
Advanced Functional Materials | Year: 2015

A facile yet effective chemical vapor deposition (CVD) method to prepare carbon nanomesh (CNM) with MgAl-layered double oxides (LDO) as sacrificial template and ferrocene as carbon precursor is reported. Due to the combined effect of the LDO template and organometallic precursor, the as-made hexagonal thin-sheet CNM features a hierarchical pore system consisting of micropores and small mesopores with a size range of 1-6 nm, and a great number of random large mesopores with a pore size of 10-50 nm. The density, geometry, and size of the pores are strongly dependent on the CVD time and the annealing conditions. As supercapacitor electrode, the CNM exhibits an enhanced capacitance, high rate capability, and outstanding cycling performance with a much-shortened time constant. The excellent capacitive performance is due to the presence of the large mesopores in the 2D CNM, which not only offer additional ion channels to accelerate the diffusion rate across the thin sheets but also help to make efficient use of the oxygen functional groups at the edges of large mesopores to increase the pseudocapacitance contribution. Growth of thin-sheet carbon nanomesh (CNM) on MgAl-layered double oxides, with controllable in-plane pore structure, is reported. The large mesopores with pore size varying from 10 to 50 nm offer additional ion channels that greatly promote ion kinetics across the 2D CNM plane, leading to an improved capacitive performance with much shortened relaxation time constant. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Wang X.,Dalian University of Technology | Wang X.,Carbon Research Laboratory | Xu W.,Dalian University of Technology | Liu N.,Dalian University of Technology | And 3 more authors.
Catalysis Today | Year: 2015

Graphene sheets (GS) supported monometal (Ni, Co) or bimetal (Ni-Co) nanoparticle composites have been conveniently prepared with the assistance of dielectric barrier discharge (DBD) plasma at low temperature. Both graphene oxide and the metal ions (Ni2+, Co2+) can be simultaneously reduced during the DBD plasma treatment in H2 atmosphere, which gives rise to the uniformly distributed metal nanoparticles on the surface of GS. The graphene-based catalysts are used in the catalytic hydrodesulfurization (HDS) of carbonyl sulfide (COS). It is revealed that the bimetallic Ni-Co/GS catalyst exhibits outstanding performance for higher COS conversion compared with the monometal catalysts, suggesting the synergetic effect between Ni and Co active species in the HDS reaction. The presented strategy demonstrates a new pathway for the preparation of graphene-based catalysts with high HDS catalytic performance. © 2015 Elsevier B.V. Source

Xiao N.,Carbon Research Laboratory | Zhou Y.,Carbon Research Laboratory | Qiu J.,Carbon Research Laboratory | Qiu J.,Dalian University of Technology | Wang Z.,Qingdao University
Fuel | Year: 2010

Carbon nanofibers/carbon foam composites that are made by growing carbon nanofibers (CNFs) on the surface of a carbon foam (CF) have been prepared from coal liquefaction residues (CLR) by a procedure involving supercritical foaming, oxidization, carbonization, and catalytic chemical vapour deposition (CCVD) treatment. These new carbon/carbon composites were examined using SEM, TEM and XRD. The results show that the as-made CF has a structure with cell sizes of 300-600 μm. X-ray diffraction studies show that iron-containing contaminates are present in the CLR. However, these species may act as a catalyst in the CCVD process as established in the literature. After the CCVD treatment, the cell walls of CF are covered by highly compacted CNFs that have external diameters of about 100 nm and lengths of several tens of micrometers. This work may open a new way for direct and effective utilization of the CLR. © 2009 Elsevier Ltd. All rights reserved. Source

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