Institute of the Chinese Academy of Sciences metal Shenyang National Laboratory for Materials Science (joint) research laboratory researcher at the advanced carbon-ming, an associate research fellow at doctoral student Li Feng and Wang Dawei, such as Australia and the University of Queensland Professor Lu HD cooperation in the National Natural Science Fund support of the design and prepared a local level porous graphite three-dimensional structure of a new type of porous carbon (Hierarchical Porous Graphitic Carbon, HPGC). The material in the high-rate conditions at the same time have a high energy density and power density, super capacitors can be used as electrode material, the relevant papers recently in Angewandte Chemie International Edition (47,373-376,2008) in 1998.
In the high-rate development under the conditions of high energy / high power density of porous carbon with carbon energy is a key player in the direction of research. Based on such material storage devices - super capacitors, and hybrid vehicles and electric vehicles is closely related to the development. At present, however, reported porous carbon energy density and power density in the high-rate conditions are usually quickly decay, it is difficult to meet, such as electric vehicles on the supercapacitor high energy, high power density of the pressing needs.
The group studied in the porous carbon electrodes in the basic electrochemical process, found that the porous electrode charge storage capacity from the porous structure of ion transport properties of porous carbons, electrically conductive electrolyte, as well as the nature and between the electrolyte and carbon physical and chemical factors such as determined by the interaction. Accordingly, they proposed different scales hole assembly in the form of three-dimensional network, to the extent possible, access to local lamellar structure of graphite electrode materials design. Its design principle is: Graphite local level porous structure of the three-dimensional (HPGC structure) can take full advantage of the pore structure of a quasi-phase electrolyte storage tank to reduce the ion diffusion distance, in the pore structure provides fast ion transport channel, big hole - hole synergies can be realized electrolyte ions in the porous carbon electrodes in the quasi-phase fast-spreading; microporous high electrostatic adsorption capacity gives excellent electrochemical energy storage activity; Local graphite layers will be able to improve the material Ontology electrically conductive. HPGC structure can be effectively increase the availability of ion electrochemical activity of specific surface area and electrochemical activity, and significantly reduce the current polarization of the lead, which was agreed under the conditions of high-rate high-energy, high power density of electrochemical energy storage and conversion capacity. HPGC many characteristics of the structure of their preparation has been very difficult. To this end, the researchers made use of liquid inorganic template, prepared with the big hole - hole - three-dimensional microporous structure and local-level lamellar structure of graphite HPGC materials. The experimental results show that, compared HPGC materials ordered mesoporous activated carbon and carbon is more outstanding high-rate electrochemical energy storage and conversion. Excellent high-rate performance in the storage of water and organic electrolyte can be achieved, the performance of the United States over the PNGV (the Partnership for a New Generation of Vehicle) power indicators. If electrolyte further enhance the work of voltage, while maintaining superior power density PNGV indicators, it is also is expected to achieve a higher energy density. These results suggest that local levels of three-dimensional porous graphite carbon structure is expected to become a super capacitor electric vehicle with excellent electrode materials.
In addition, the inorganic liquid or a universal template method of porous materials synthesis methods. By adjusting the template material physical and chemical properties, can be a different structure and physico-chemical properties such as magnetic, and the level of carbon-carbon composites, these materials in magnetic separation, catalysis, and other clean energy and environmental protection field has broad application prospects .
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