碳化聚丙烯腈多孔材料在电化学电容器中的应用研究

CARBON FOAM MATERIALS PREPARED FROM POLYACRYLONITRILE AND THEIR APPLICATION IN ELECTROCHEMICAL CAPACITORS

Porous membranes of polyacry lonitrile were prepared directly on carbon paper with the phase inversion method,and then cross-linked under γ-ray radiation.Carbon foam materials were obtained from these cross-linked composite porous membranes after oxidation at 220℃ in air,carbonization at 850℃ in nitrogen and activation at 850℃ in CO-2.Morphologies of the carbon foam materials were observed with scanning electron microscopy,and the specific surface area was measured with the Brunauer-Emmett-Teller(BET) technique.It was found that the network structure of the carbon foam materials was affected by γ-ray radiation,and that the BET value could reach a high value of 500 m+2/g after treatment with CO-2 at 850℃.These carbon foam materials can be used directly as electrodes of electrochemical capacitors in suitable shapes and size.Cyclic voltammetry,AC impedance spectrum and galvanic cycles of the carbon foam electrode were tested both in aqueous and organic media for evaluating its electrochemical performance.The results show that the specific capacitance of such a carbon foam electrode in 1 mol/L aqueous solution of sulfuric acid is 174 F/g,which is at the high level of carbon electrodes.

Porous membranes of polyacry lonitrile were prepared directly on carbon paper with the phase inversion method, and then cross-linked under gamma-ray radiation. Carbon foam materials were obtained from these cross-linked composite porous membranes after oxidation at 220degreesC in air, carbonization at 850degreesC in nitrogen and activation at 850degreesC in CO2 Morphologies of the carbon foam materials were observed with scanning electron microscopy, and the specific surface area was measured with the Brunauer-Emmett-Teller( BET) technique. It was found that the network structure of the carbon foam materials was affected by gamma-ray radiation, and that the BET value could reach a high value of 500 m(2)/g after treatment with CO2 at 850degreesC. These carbon foam materials can be used directly as electrodes of electrochemical capacitors in suitable shapes and size. Cyclic voltammetry, AC impedance spectrum and galvanic cycles of the carbon foam electrode were tested both in aqueous and organic media for evaluating its electrochemical performance. The results show that the specific capacitance of such a carbon foam electrode in 1 mol/L aqueous solution of sulfuric acid is 174 F/g, which is at the high level of carbon electrodes.